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GPG2(1)                        GNU Privacy Guard                       GPG2(1)



NAME
       gpg2 - OpenPGP encryption and signing tool

SYNOPSIS
       gpg2 [--homedir dir] [--options file] [options] command [args]


DESCRIPTION
       gpg2 is the OpenPGP part of the GNU Privacy Guard (GnuPG). It is a tool to provide digital encryption and sign-
       ing services using the OpenPGP standard. gpg2 features complete key management and all bells and  whistles  you
       can expect from a decent OpenPGP implementation.


       In contrast to the standalone version gpg, which is more suited for server and embedded platforms, this version
       is installed under the name gpg2 and more targeted to the desktop as it requires several other  modules  to  be
       installed.   The  standalone version will be kept maintained and it is possible to install both versions on the
       same system.  If you need to use  different  configuration  files,  you  should  make  use  of  something  like
       'gpg.conf-2' instead of just 'gpg.conf'.







RETURN VALUE
       The  program  returns  0  if  everything was fine, 1 if at least a signature was bad, and other error codes for
       fatal errors.


WARNINGS
       Use a *good* password for your user account and a *good* passphrase to protect your secret key. This passphrase
       is the weakest part of the whole system. Programs to do dictionary attacks on your secret keyring are very easy
       to write and so you should protect your "~/.gnupg/" directory very well.

       Keep in mind that, if this program is used over a  network  (telnet),  it  is  *very*  easy  to  spy  out  your
       passphrase!

       If  you  are  going  to verify detached signatures, make sure that the program knows about it; either give both
       filenames on the command line or use '-' to specify STDIN.


INTEROPERABILITY
       GnuPG tries to be a very flexible implementation of the OpenPGP standard. In particular, GnuPG implements  many
       of the optional parts of the standard, such as the SHA-512 hash, and the ZLIB and BZIP2 compression algorithms.
       It is important to be aware that not all OpenPGP programs implement these optional algorithms and that by forc-
       ing their use via the --cipher-algo, --digest-algo, --cert-digest-algo, or --compress-algo options in GnuPG, it
       is possible to create a perfectly valid OpenPGP message, but one that cannot be read by the intended recipient.

       There  are dozens of variations of OpenPGP programs available, and each supports a slightly different subset of
       these optional algorithms.  For example, until recently, no (unhacked) version of PGP  supported  the  BLOWFISH
       cipher  algorithm.  A message using BLOWFISH simply could not be read by a PGP user. By default, GnuPG uses the
       standard OpenPGP preferences system that will always do the right thing and create messages that are usable  by
       all  recipients,  regardless  of  which OpenPGP program they use. Only override this safe default if you really
       know what you are doing.

       If you absolutely must override the safe default, or if the preferences on a given key  are  invalid  for  some
       reason,  you  are far better off using the --pgp6, --pgp7, or --pgp8 options. These options are safe as they do
       not force any particular algorithms in violation of OpenPGP, but rather reduce the available  algorithms  to  a
       "PGP-safe" list.


COMMANDS
       Commands are not distinguished from options except for the fact that only one command is allowed.

       gpg2  may  be  run with no commands, in which case it will perform a reasonable action depending on the type of
       file it is given as input (an encrypted message is decrypted, a signature is verified, a file  containing  keys
       is listed).

       Please  remember  that  option as well as command parsing stops as soon as a non-option is encountered, you can
       explicitly stop parsing by using the special option --.






   Commands not specific to the function



       --version
              Print the program version and licensing information.  Note that you cannot abbreviate this command.


       --help

       -h     Print a usage message summarizing the most useful command line options.  Note that you cannot abbreviate
              this command.


       --warranty
              Print warranty information.


       --dump-options
              Print a list of all available options and commands.  Note that you cannot abbreviate this command.




   Commands to select the type of operation





       --sign

       -s     Make  a  signature.  This  command  may be combined with --encrypt (for a signed and encrypted message),
              --symmetric (for a signed and symmetrically encrypted message), or --encrypt  and  --symmetric  together
              (for  a  signed message that may be decrypted via a secret key or a passphrase).  The key to be used for
              signing is chosen by default or can be set with the --local-user and --default-key options.


       --clearsign
              Make a clear text signature.  The content in a clear text signature  is  readable  without  any  special
              software.  OpenPGP  software  is  only needed to verify the signature.  Clear text signatures may modify
              end-of-line whitespace for platform independence and are not intended to be reversible.  The key  to  be
              used for signing is chosen by default or can be set with the --local-user and --default-key options.



       --detach-sign

       -b     Make a detached signature.


       --encrypt

       -e     Encrypt  data. This option may be combined with --sign (for a signed and encrypted message), --symmetric
              (for a message that may be decrypted via a secret key  or  a  passphrase),  or  --sign  and  --symmetric
              together (for a signed message that may be decrypted via a secret key or a passphrase).


       --symmetric

       -c     Encrypt  with a symmetric cipher using a passphrase. The default symmetric cipher used is CAST5, but may
              be chosen with the --cipher-algo option. This option may be combined with --sign (for a signed and  sym-
              metrically  encrypted  message),  --encrypt  (for  a message that may be decrypted via a secret key or a
              passphrase), or --sign and --encrypt together (for a signed message that may be decrypted via  a  secret
              key or a passphrase).


       --store
              Store only (make a simple RFC1991 literal data packet).


       --decrypt

       -d     Decrypt the file given on the command line (or STDIN if no file is specified) and write it to STDOUT (or
              the file specified with --output). If the decrypted file is signed, the signature is also verified. This
              command  differs from the default operation, as it never writes to the filename which is included in the
              file and it rejects files which don't begin with an encrypted message.


       --verify
              Assume that the first argument is a signed file or a detached signature and verify it without generating
              any  output.  With no arguments, the signature packet is read from STDIN. If only a sigfile is given, it
              may be a complete signature or a detached signature, in which case the signed stuff  is  expected  in  a
              file  without the ".sig" or ".asc" extension.  With more than 1 argument, the first should be a detached
              signature and the remaining files are the signed stuff. To read the signed stuff from STDIN, use '-'  as
              the  second  filename.   For  security reasons a detached signature cannot read the signed material from
              STDIN without denoting it in the above way.


       --multifile
              This modifies certain other commands to accept multiple files for processing on the command line or read
              from  STDIN  with  each filename on a separate line. This allows for many files to be processed at once.
              --multifile may currently be used along with --verify, --encrypt, and --decrypt. Note  that  --multifile
              --verify may not be used with detached signatures.


       --verify-files
              Identical to --multifile --verify.


       --encrypt-files
              Identical to --multifile --encrypt.


       --decrypt-files
              Identical to --multifile --decrypt.


       --list-keys

       -k

       --list-public-keys
              List all keys from the public keyrings, or just the keys given on the command line.

              Avoid  using  the output of this command in scripts or other programs as it is likely to change as GnuPG
              changes. See --with-colons for a machine-parseable key listing command that is appropriate  for  use  in
              scripts and other programs.


       --list-secret-keys

       -K     List  all  keys from the secret keyrings, or just the ones given on the command line. A # after the let-
              ters sec means that the secret key is not usable (for example, if it was  created  via  --export-secret-
              subkeys).


       --list-sigs
              Same  as  --list-keys,  but  the  signatures  are listed too.  This command has the same effect as using
              --list-keys with --with-sig-list.

              For each signature listed, there are several flags in between the "sig" tag and keyid. These flags  give
              additional  information  about each signature. From left to right, they are the numbers 1-3 for certifi-
              cate check level (see --ask-cert-level), "L" for a local or non-exportable signature (see  --lsign-key),
              "R"  for  a  nonRevocable signature (see the --edit-key command "nrsign"), "P" for a signature that con-
              tains a policy URL (see --cert-policy-url), "N" for a signature that contains a  notation  (see  --cert-
              notation),  "X"  for an eXpired signature (see --ask-cert-expire), and the numbers 1-9 or "T" for 10 and
              above to indicate trust signature levels (see the --edit-key command "tsign").


       --check-sigs
              Same as --list-sigs, but the signatures are verified.  Note that for performance reasons the  revocation
              status  of  a  signing  key  is  not  shown.  This command has the same effect as using --list-keys with
              --with-sig-check.

              The status of the verification is indicated by a flag directly following the "sig" tag (and thus  before
              the  flags  described  above for --list-sigs).  A "!" indicates that the signature has been successfully
              verified, a "-" denotes a bad signature and a "%" is used if an error occurred while checking the signa-
              ture (e.g. a non supported algorithm).


       --locate-keys
              Locate  the keys given as arguments.  This command basically uses the same algorithm as used when locat-
              ing keys for encryption or signing and may thus be used to see what keys gpg2 might use.  In  particular
              external  methods  as  defined  by  --auto-key-locate may be used to locate a key.  Only public keys are
              listed.



       --fingerprint
              List all keys (or the specified ones) along with their fingerprints. This is the same output as  --list-
              keys  but  with  the additional output of a line with the fingerprint. May also be combined with --list-
              sigs or --check-sigs.  If this command is given twice, the fingerprints of all secondary keys are listed
              too.


       --list-packets
              List only the sequence of packets. This is mainly useful for debugging.



       --card-edit
              Present  a  menu  to work with a smartcard. The subcommand "help" provides an overview on available com-
              mands. For a detailed description, please see the Card HOWTO at  http://www.gnupg.org/documentation/how-
              tos.html#GnuPG-cardHOWTO .


       --card-status
              Show the content of the smart card.


       --change-pin
              Present  a  menu  to  allow changing the PIN of a smartcard. This functionality is also available as the
              subcommand "passwd" with the --card-edit command.


       --delete-key name
              Remove key from the public keyring. In batch mode either --yes is required or the key must be  specified
              by fingerprint. This is a safeguard against accidental deletion of multiple keys.


       --delete-secret-key name
              Remove key from the secret and public keyring. In batch mode the key must be specified by fingerprint.


       --delete-secret-and-public-key name
              Same  as  --delete-key, but if a secret key exists, it will be removed first. In batch mode the key must
              be specified by fingerprint.


       --export
              Either export all keys from all keyrings (default keyrings and those registered via  option  --keyring),
              or  if  at  least one name is given, those of the given name. The new keyring is written to STDOUT or to
              the file given with option --output. Use together with --armor to mail those keys.


       --send-keys key IDs
              Similar to --export but sends the keys to a keyserver.  Fingerprints may be used  instead  of  key  IDs.
              Option  --keyserver must be used to give the name of this keyserver. Don't send your complete keyring to
              a keyserver --- select only those keys which are new or changed by you.  If no key IDs  are  given,  gpg
              does nothing.


       --export-secret-keys

       --export-secret-subkeys
              Same  as --export, but exports the secret keys instead.  This is normally not very useful and a security
              risk.  The second form of the command has the special property to render the secret part of the  primary
              key  useless;  this  is a GNU extension to OpenPGP and other implementations can not be expected to suc-
              cessfully import such a key.  See the option --simple-sk-checksum if you want to import such an exported
              key with an older OpenPGP implementation.


       --import

       --fast-import
              Import/merge  keys.  This  adds the given keys to the keyring. The fast version is currently just a syn-
              onym.

              There are a few other options which control how this command works.  Most notable here is the  --import-
              options  merge-only  option  which does not insert new keys but does only the merging of new signatures,
              user-IDs and subkeys.


       --recv-keys key IDs
              Import the keys with the given key IDs from a keyserver. Option --keyserver must be  used  to  give  the
              name of this keyserver.


       --refresh-keys
              Request  updates  from  a keyserver for keys that already exist on the local keyring. This is useful for
              updating a key with the latest signatures, user IDs, etc. Calling this with no  arguments  will  refresh
              the  entire keyring. Option --keyserver must be used to give the name of the keyserver for all keys that
              do not have preferred keyservers set (see --keyserver-options honor-keyserver-url).


       --search-keys names
              Search the keyserver for the given names. Multiple names given here will be joined  together  to  create
              the  search  string  for  the  keyserver.  Option --keyserver must be used to give the name of this key-
              server.  Keyservers that support different search methods allow using the syntax specified  in  "How  to
              specify  a  user  ID"  below.  Note  that  different  keyserver  types support different search methods.
              Currently only LDAP supports them all.


       --fetch-keys URIs
              Retrieve keys located at the specified URIs. Note that different installations of GnuPG may support dif-
              ferent protocols (HTTP, FTP, LDAP, etc.)


       --update-trustdb
              Do  trust database maintenance. This command iterates over all keys and builds the Web of Trust. This is
              an interactive command because it may have to ask for the "ownertrust" values for keys. The user has  to
              give  an  estimation  of  how  far she trusts the owner of the displayed key to correctly certify (sign)
              other keys. GnuPG only asks for the ownertrust value if it has not yet been assigned to a key. Using the
              --edit-key menu, the assigned value can be changed at any time.


       --check-trustdb
              Do  trust  database  maintenance  without user interaction. From time to time the trust database must be
              updated so that expired keys or signatures and the resulting changes in the Web of Trust can be tracked.
              Normally,  GnuPG  will  calculate  when this is required and do it automatically unless --no-auto-check-
              trustdb is set. This command can be used to force a trust database check at any time. The processing  is
              identical to that of --update-trustdb but it skips keys with a not yet defined "ownertrust".

              For  use with cron jobs, this command can be used together with --batch in which case the trust database
              check is done only if a check is needed. To force a run even in batch mode add the option --yes.



       --export-ownertrust
              Send the ownertrust values to STDOUT. This is useful for backup purposes as these values  are  the  only
              ones which can't be re-created from a corrupted trustdb.  Example:
                  gpg2 --export-ownertrust > otrust.txt



       --import-ownertrust
              Update  the  trustdb with the ownertrust values stored in files (or STDIN if not given); existing values
              will be overwritten.  In case of a severely damaged trustdb and if you have a recent backup of the  own-
              ertrust values (e.g. in the file 'otrust.txt', you may re-create the trustdb using these commands:
                  cd ~/.gnupg
                  rm trustdb.gpg
                  gpg2 --import-ownertrust < otrust.txt



       --rebuild-keydb-caches
              When  updating from version 1.0.6 to 1.0.7 this command should be used to create signature caches in the
              keyring. It might be handy in other situations too.


       --print-md algo

       --print-mds
              Print message digest of algorithm ALGO for all given files or STDIN.  With the second form (or a  depre-
              cated "*" as algo) digests for all available algorithms are printed.


       --gen-random 0|1|2
              Emit  count  random bytes of the given quality level. If count is not given or zero, an endless sequence
              of random bytes will be emitted.  PLEASE, don't use this command unless you know what you are doing;  it
              may remove precious entropy from the system!


       --gen-prime mode bits
              Use the source, Luke :-). The output format is still subject to change.



       --enarmor

       --dearmor
              Pack  or  unpack  an  arbitrary  input  into/from  an OpenPGP ASCII armor.  This is a GnuPG extension to
              OpenPGP and in general not very useful.





   How to manage your keys


       This section explains the main commands for key management



       --gen-key
              Generate a new key pair. This command is normally only used interactively.

              There is an experimental feature  which  allows  you  to  create  keys  in  batch  mode.  See  the  file
              'doc/DETAILS' in the source distribution on how to use this.


       --gen-revoke name
              Generate  a  revocation  certificate  for  the  complete key. To revoke a subkey or a signature, use the
              --edit command.


       --desig-revoke name
              Generate a designated revocation certificate for a key. This allows a user (with the permission  of  the
              keyholder) to revoke someone else's key.



       --edit-key
              Present  a menu which enables you to do most of the key management related tasks.  It expects the speci-
              fication of a key on the command line.



              uid n  Toggle selection of user ID or photographic user ID with index n.  Use * to select all and  0  to
                     deselect all.


              key n  Toggle selection of subkey with index n.  Use * to select all and 0 to deselect all.


              sign   Make  a  signature  on  key of user name If the key is not yet signed by the default user (or the
                     users given with -u), the program displays the information of the key again,  together  with  its
                     fingerprint  and asks whether it should be signed. This question is repeated for all users speci-
                     fied with -u.


              lsign  Same as "sign" but the signature is marked as non-exportable and will therefore never be used  by
                     others. This may be used to make keys valid only in the local environment.


              nrsign Same as "sign" but the signature is marked as non-revocable and can therefore never be revoked.


              tsign  Make  a  trust  signature. This is a signature that combines the notions of certification (like a
                     regular signature), and trust (like the "trust" command). It is generally only useful in distinct
                     communities or groups.

              Note  that  "l" (for local / non-exportable), "nr" (for non-revocable, and "t" (for trust) may be freely
              mixed and prefixed to "sign" to create a signature of any type desired.



              delsig Delete a signature. Note that it is not possible to retract a signature, once it has been send to
                     the public (i.e. to a keyserver).  In that case you better use revsig.


              revsig Revoke a signature. For every signature which has been generated by one of the secret keys, GnuPG
                     asks whether a revocation certificate should be generated.


              check  Check the signatures on all selected user IDs.


              adduid Create an additional user ID.


              addphoto
                     Create a photographic user ID. This will prompt for a JPEG file that will be  embedded  into  the
                     user ID. Note that a very large JPEG will make for a very large key. Also note that some programs
                     will display your JPEG unchanged (GnuPG), and some programs will scale it to fit in a dialog  box
                     (PGP).


              showphoto
                     Display the selected photographic user ID.


              deluid Delete  a  user  ID  or photographic user ID.  Note that it is not possible to retract a user id,
                     once it has been send to the public (i.e. to a keyserver).  In that case you better use revuid.


              revuid Revoke a user ID or photographic user ID.


              primary
                     Flag the current user id as the primary one, removes the primary user id flag from all other user
                     ids  and sets the timestamp of all affected self-signatures one second ahead. Note that setting a
                     photo user ID as primary makes it primary over other photo user IDs, and setting a  regular  user
                     ID as primary makes it primary over other regular user IDs.


              keyserver
                     Set a preferred keyserver for the specified user ID(s). This allows other users to know where you
                     prefer they get your key from. See --keyserver-options honor-keyserver-url for more on  how  this
                     works.  Setting a value of "none" removes an existing preferred keyserver.


              notation
                     Set  a name=value notation for the specified user ID(s). See --cert-notation for more on how this
                     works. Setting a value of "none" removes all notations, setting a notation prefixed with a  minus
                     sign  (-) removes that notation, and setting a notation name (without the =value) prefixed with a
                     minus sign removes all notations with that name.


              pref   List preferences from the selected user ID. This shows the actual preferences, without  including
                     any implied preferences.


              showpref
                     More  verbose  preferences listing for the selected user ID. This shows the preferences in effect
                     by including the implied preferences of 3DES (cipher), SHA-1 (digest), and Uncompressed (compres-
                     sion)  if  they  are not already included in the preference list. In addition, the preferred key-
                     server and signature notations (if any) are shown.


              setpref string
                     Set the list of user ID preferences to string for all (or just the selected)  user  IDs.  Calling
                     setpref  with  no  arguments  sets the preference list to the default (either built-in or set via
                     --default-preference-list), and calling setpref with "none" as the argument sets an empty prefer-
                     ence  list.  Use  gpg2  --version  to get a list of available algorithms. Note that while you can
                     change the preferences on an attribute user ID (aka "photo ID"), GnuPG does not select  keys  via
                     attribute user IDs so these preferences will not be used by GnuPG.

                     When  setting  preferences,  you  should list the algorithms in the order which you'd like to see
                     them used by someone else when encrypting a message to your key.  If you don't include  3DES,  it
                     will  be  automatically added at the end.  Note that there are many factors that go into choosing
                     an algorithm (for example, your key may not be the only recipient), and  so  the  remote  OpenPGP
                     application  being  used to send to you may or may not follow your exact chosen order for a given
                     message.  It will, however, only choose an algorithm that is present on the  preference  list  of
                     every recipient key.  See also the INTEROPERABILITY WITH OTHER OPENPGP PROGRAMS section below.


              addkey Add a subkey to this key.


              addcardkey
                     Generate a subkey on a card and add it to this key.


              keytocard
                     Transfer  the  selected  secret  subkey  (or the primary key if no subkey has been selected) to a
                     smartcard. The secret key in the keyring will be replaced by a stub if the key  could  be  stored
                     successfully on the card and you use the save command later. Only certain key types may be trans-
                     ferred to the card. A sub menu allows you to select on what card to store the key. Note  that  it
                     is not possible to get that key back from the card - if the card gets broken your secret key will
                     be lost unless you have a backup somewhere.


              bkuptocard file
                     Restore the given file to a card. This command may be used to restore a backup key (as  generated
                     during  card  initialization) to a new card. In almost all cases this will be the encryption key.
                     You should use this command only with the corresponding public key and make sure  that  the  file
                     given as argument is indeed the backup to restore. You should then select 2 to restore as encryp-
                     tion key.  You will first be asked to enter the passphrase of the backup key  and  then  for  the
                     Admin PIN of the card.


              delkey Remove  a  subkey  (secondart key). Note that it is not possible to retract a subkey, once it has
                     been send to the public (i.e. to a keyserver).  In that case you better use revkey.


              revkey Revoke a subkey.


              expire Change the key or subkey expiration time. If a subkey is selected, the expiration  time  of  this
                     subkey will be changed. With no selection, the key expiration of the primary key is changed.


              trust  Change  the  owner  trust value for the key. This updates the trust-db immediately and no save is
                     required.


              disable

              enable Disable or enable an entire key. A disabled key can not normally be used for encryption.


              addrevoker
                     Add a designated revoker to the key. This takes one optional argument: "sensitive". If  a  desig-
                     nated revoker is marked as sensitive, it will not be exported by default (see export-options).


              passwd Change the passphrase of the secret key.


              toggle Toggle between public and secret key listing.


              clean  Compact  (by  removing  all  signatures  except the selfsig) any user ID that is no longer usable
                     (e.g. revoked, or expired). Then, remove any signatures that are not usable by the trust calcula-
                     tions.   Specifically,  this  removes any signature that does not validate, any signature that is
                     superseded by a later signature, revoked signatures, and signatures issued by keys that  are  not
                     present on the keyring.


              minimize
                     Make  the  key as small as possible. This removes all signatures from each user ID except for the
                     most recent self-signature.


              cross-certify
                     Add cross-certification signatures to signing subkeys that may not currently  have  them.  Cross-
                     certification  signatures protect against a subtle attack against signing subkeys. See --require-
                     cross-certification.  All new keys generated have this signature by default, so  this  option  is
                     only useful to bring older keys up to date.


              save   Save all changes to the key rings and quit.


              quit   Quit the program without updating the key rings.


              The  listing  shows  you the key with its secondary keys and all user ids. Selected keys or user ids are
              indicated by an asterisk. The trust value is displayed with the primary key: the first is  the  assigned
              owner trust and the second is the calculated trust value. Letters are used for the values:



              -      No ownertrust assigned / not yet calculated.


              e      Trust calculation has failed; probably due to an expired key.


              q      Not enough information for calculation.


              n      Never trust this key.


              m      Marginally trusted.


              f      Fully trusted.


              u      Ultimately trusted.


       --sign-key name
              Signs  a  public  key  with  your  secret  key. This is a shortcut version of the subcommand "sign" from
              --edit.


       --lsign-key name
              Signs a public key with your secret key but marks it as non-exportable. This is a  shortcut  version  of
              the subcommand "lsign" from --edit-key.






OPTIONS
       gpg2  comes features a bunch of options to control the exact behaviour and to change the default configuration.


       Long options can be put in an options file (default "~/.gnupg/gpg.conf"). Short option names will  not  work  -
       for  example,  "armor" is a valid option for the options file, while "a" is not. Do not write the 2 dashes, but
       simply the name of the option and any required arguments. Lines with a hash ('#') as the first  non-white-space
       character  are  ignored.  Commands may be put in this file too, but that is not generally useful as the command
       will execute automatically with every execution of gpg.

       Please remember that option parsing stops as soon as a non-option is encountered, you can explicitly stop pars-
       ing by using the special option --.



   How to change the configuration


       These options are used to change the configuration and are usually found in the option file.



       --default-key name
              Use  name  as the default key to sign with. If this option is not used, the default key is the first key
              found in the secret keyring.  Note that -u or --local-user overrides this option.


       --default-recipient name
              Use name as default recipient if option --recipient is not used and don't ask if this is  a  valid  one.
              name must be non-empty.


       --default-recipient-self
              Use  the  default  key as default recipient if option --recipient is not used and don't ask if this is a
              valid one. The default key is the first one from the secret keyring or the one set with --default-key.


       --no-default-recipient
              Reset --default-recipient and --default-recipient-self.


       -v, --verbose
              Give more information during processing. If used twice, the input data is listed in detail.


       --no-verbose
              Reset verbose level to 0.


       -q, --quiet
              Try to be as quiet as possible.


       --batch

       --no-batch
              Use batch mode.  Never ask, do not allow interactive commands.  --no-batch disables this  option.   Note
              that even with a filename given on the command line, gpg might still need to read from STDIN (in partic-
              ular if gpg figures that the input is a detached signature and no data file has been  specified).   Thus
              if you do not want to feed data via STDIN, you should connect STDIN to '/dev/null'.


       --no-tty
              Make  sure  that  the  TTY (terminal) is never used for any output.  This option is needed in some cases
              because GnuPG sometimes prints warnings to the TTY even if --batch is used.


       --yes  Assume "yes" on most questions.


       --no   Assume "no" on most questions.



       --list-options parameters
              This is a space or comma delimited string that gives options used when listing keys and signatures (that
              is,  --list-keys,  --list-sigs,  --list-public-keys,  --list-secret-keys, and the --edit-key functions).
              Options can be prepended with a no- (after the two dashes) to give the opposite  meaning.   The  options
              are:



              show-photos
                     Causes  --list-keys, --list-sigs, --list-public-keys, and --list-secret-keys to display any photo
                     IDs attached to the key.  Defaults to no. See also --photo-viewer.


              show-policy-urls
                     Show policy URLs in the --list-sigs or --check-sigs listings.  Defaults to no.


              show-notations

              show-std-notations

              show-user-notations
                     Show all, IETF standard, or user-defined signature notations in the --list-sigs  or  --check-sigs
                     listings. Defaults to no.


              show-keyserver-urls

                     Show any preferred keyserver URL in the --list-sigs or --check-sigs listings. Defaults to no.


              show-uid-validity
                     Display the calculated validity of user IDs during key listings.  Defaults to no.


              show-unusable-uids
                     Show revoked and expired user IDs in key listings. Defaults to no.


              show-unusable-subkeys
                     Show revoked and expired subkeys in key listings. Defaults to no.


              show-keyring
                     Display  the  keyring  name at the head of key listings to show which keyring a given key resides
                     on. Defaults to no.


              show-sig-expire
                     Show signature expiration dates (if any) during --list-sigs or --check-sigs listings. Defaults to
                     no.


              show-sig-subpackets
                     Include  signature  subpackets in the key listing. This option can take an optional argument list
                     of the subpackets to list. If no argument is passed, list all subpackets. Defaults  to  no.  This
                     option is only meaningful when using --with-colons along with --list-sigs or --check-sigs.


       --verify-options parameters
              This is a space or comma delimited string that gives options used when verifying signatures. Options can
              be prepended with a 'no-' to give the opposite meaning. The options are:



              show-photos
                     Display any photo IDs present on the key that issued the signature.  Defaults  to  no.  See  also
                     --photo-viewer.


              show-policy-urls
                     Show policy URLs in the signature being verified. Defaults to no.


              show-notations

              show-std-notations

              show-user-notations
                     Show  all,  IETF  standard,  or user-defined signature notations in the signature being verified.
                     Defaults to IETF standard.


              show-keyserver-urls
                     Show any preferred keyserver URL in the signature being verified.  Defaults to no.


              show-uid-validity
                     Display the calculated validity of the user IDs on the key that issued the signature. Defaults to
                     no.


              show-unusable-uids
                     Show revoked and expired user IDs during signature verification.  Defaults to no.


              show-primary-uid-only
                     Show  only  the primary user ID during signature verification.  That is all the AKA lines as well
                     as photo Ids are not shown with the signature verification status.


              pka-lookups
                     Enable PKA lookups to verify sender addresses. Note that PKA is based on  DNS,  and  so  enabling
                     this  option may disclose information on when and what signatures are verified or to whom data is
                     encrypted. This is similar to the "web bug" described for the auto-key-retrieve feature.


              pka-trust-increase
                     Raise the trust in a signature to full if the signature passes PKA  validation.  This  option  is
                     only meaningful if pka-lookups is set.


       --enable-dsa2

       --disable-dsa2
              Enable  hash truncation for all DSA keys even for old DSA Keys up to 1024 bit.  This is also the default
              with --openpgp.  Note that older versions of GnuPG also required this flag to allow  the  generation  of
              DSA larger than 1024 bit.


       --photo-viewer string
              This is the command line that should be run to view a photo ID. "%i" will be expanded to a filename con-
              taining the photo. "%I" does the same, except the file will not be deleted once the viewer exits.  Other
              flags  are  "%k"  for  the  key ID, "%K" for the long key ID, "%f" for the key fingerprint, "%t" for the
              extension of the image type (e.g. "jpg"), "%T" for the MIME type of the image (e.g.  "image/jpeg"),  and
              "%%" for an actual percent sign. If neither %i or %I are present, then the photo will be supplied to the
              viewer on standard input.

              The default viewer is "xloadimage -fork -quiet -title 'KeyID 0x%k'  STDIN".  Note  that  if  your  image
              viewer program is not secure, then executing it from GnuPG does not make it secure.


       --exec-path string
              Sets a list of directories to search for photo viewers and keyserver helpers. If not provided, keyserver
              helpers use the compiled-in default directory, and photo viewers use  the  $PATH  environment  variable.
              Note, that on W32 system this value is ignored when searching for keyserver helpers.


       --keyring file
              Add file to the current list of keyrings. If file begins with a tilde and a slash, these are replaced by
              the $HOME directory. If the filename does not contain a slash, it is assumed to be  in  the  GnuPG  home
              directory ("~/.gnupg" if --homedir or $GNUPGHOME is not used).

              Note  that this adds a keyring to the current list. If the intent is to use the specified keyring alone,
              use --keyring along with --no-default-keyring.


       --secret-keyring file
              Same as --keyring but for the secret keyrings.


       --primary-keyring file
              Designate file as the primary public keyring. This means that newly imported keys (via --import or  key-
              server --recv-from) will go to this keyring.


       --trustdb-name file
              Use  file instead of the default trustdb. If file begins with a tilde and a slash, these are replaced by
              the $HOME directory. If the filename does not contain a slash, it is assumed to be  in  the  GnuPG  home
              directory ('~/.gnupg' if --homedir or $GNUPGHOME is not used).


       --homedir dir
              Set  the  name  of the home directory to dir. If this option is not used, the home directory defaults to
              '~/.gnupg'.  It is only recognized when given on the command line.  It also overrides any home directory
              stated  through  the environment variable 'GNUPGHOME' or (on W32 systems) by means of the Registry entry
              HKCU\Software\GNU\GnuPG:HomeDir.







       --display-charset name
              Set the name of the native character set. This is used to convert some informational strings  like  user
              IDs to the proper UTF-8 encoding.  Note that this has nothing to do with the character set of data to be
              encrypted or signed; GnuPG does not recode user-supplied data. If this option is not used,  the  default
              character set is determined from the current locale. A verbosity level of 3 shows the chosen set.  Valid
              values for name are:



              iso-8859-1
                     This is the Latin 1 set.


              iso-8859-2
                     The Latin 2 set.


              iso-8859-15
                     This is currently an alias for the Latin 1 set.


              koi8-r The usual Russian set (rfc1489).


              utf-8  Bypass all translations and assume that the OS uses native UTF-8 encoding.


       --utf8-strings

       --no-utf8-strings
              Assume that command line arguments are given as UTF8 strings.  The  default  (--no-utf8-strings)  is  to
              assume  that arguments are encoded in the character set as specified by --display-charset. These options
              affect all following arguments. Both options may be used multiple times.


       --options file
              Read options from file and do not try to read them from the default options file  in  the  homedir  (see
              --homedir). This option is ignored if used in an options file.


       --no-options
              Shortcut  for  --options  /dev/null.  This  option is detected before an attempt to open an option file.
              Using this option will also prevent the creation of a '~/.gnupg' homedir.




       -z n

       --compress-level n

       --bzip2-compress-level n
              Set compression level to n for the ZIP and ZLIB compression  algorithms.  The  default  is  to  use  the
              default  compression  level  of zlib (normally 6). --bzip2-compress-level sets the compression level for
              the BZIP2 compression algorithm (defaulting to 6 as well). This is a different option  from  --compress-
              level  since  BZIP2  uses a significant amount of memory for each additional compression level.  -z sets
              both. A value of 0 for n disables compression.


       --bzip2-decompress-lowmem
              Use a different decompression method for BZIP2 compressed files. This alternate method uses a  bit  more
              than  half  the memory, but also runs at half the speed. This is useful under extreme low memory circum-
              stances when the file was originally compressed at a high --bzip2-compress-level.



       --mangle-dos-filenames

       --no-mangle-dos-filenames
              Older version of Windows cannot handle filenames with more than one dot.  --mangle-dos-filenames  causes
              GnuPG  to  replace  (rather than add to) the extension of an output filename to avoid this problem. This
              option is off by default and has no effect on non-Windows platforms.


       --ask-cert-level

       --no-ask-cert-level
              When making a key signature, prompt for a certification level. If this option is not specified, the cer-
              tification  level  used is set via --default-cert-level. See --default-cert-level for information on the
              specific levels and how they are used. --no-ask-cert-level disables this option. This option defaults to
              no.


       --default-cert-level n
              The default to use for the check level when signing a key.

              0 means you make no particular claim as to how carefully you verified the key.

              1  means  you  believe the key is owned by the person who claims to own it but you could not, or did not
              verify the key at all. This is useful for a  "persona"  verification,  where  you  sign  the  key  of  a
              pseudonymous user.

              2  means you did casual verification of the key. For example, this could mean that you verified that the
              key fingerprint and checked the user ID on the key against a photo ID.

              3 means you did extensive verification of the key. For example, this could mean that  you  verified  the
              key  fingerprint  with the owner of the key in person, and that you checked, by means of a hard to forge
              document with a photo ID (such as a passport) that the name of the key owner matches  the  name  in  the
              user  ID  on the key, and finally that you verified (by exchange of email) that the email address on the
              key belongs to the key owner.

              Note that the examples given above for levels 2 and 3 are just that: examples. In the end, it is  up  to
              you to decide just what "casual" and "extensive" mean to you.

              This option defaults to 0 (no particular claim).


       --min-cert-level
              When building the trust database, treat any signatures with a certification level below this as invalid.
              Defaults to 2, which disregards level 1 signatures. Note that level 0 "no particular  claim"  signatures
              are always accepted.


       --trusted-key long key ID
              Assume  that the specified key (which must be given as a full 8 byte key ID) is as trustworthy as one of
              your own secret keys. This option is useful if you don't want to keep your secret keys (or one of  them)
              online but still want to be able to check the validity of a given recipient's or signator's key.


       --trust-model pgp|classic|direct|always|auto
              Set what trust model GnuPG should follow. The models are:



              pgp    This is the Web of Trust combined with trust signatures as used in PGP 5.x and later. This is the
                     default trust model when creating a new trust database.


              classic
                     This is the standard Web of Trust as used in PGP 2.x and earlier.


              direct Key validity is set directly by the user and not calculated via the Web of Trust.


              always Skip key validation and assume that used keys are always fully trusted. You generally  won't  use
                     this  unless  you  are  using  some  external  validation scheme. This option also suppresses the
                     "[uncertain]" tag printed with signature checks when there is no evidence that  the  user  ID  is
                     bound to the key.


              auto   Select  the  trust  model  depending  on  whatever  the internal trust database says. This is the
                     default model if such a database already exists.


       --auto-key-locate parameters

       --no-auto-key-locate
              GnuPG can automatically locate and retrieve keys as needed using this option. This happens when encrypt-
              ing  to an email address (in the "userATexample.com" form), and there are no userATexample.com keys on the
              local keyring.  This option takes any number of the following mechanisms, in the order they  are  to  be
              tried:



              cert   Locate a key using DNS CERT, as specified in rfc4398.


              pka    Locate a key using DNS PKA.


              ldap   Using  DNS  Service  Discovery,  check the domain in question for any LDAP keyservers to use.  If
                     this  fails,  attempt  to  locate  the  key  using  the  PGP   Universal   method   of   checking
                     'ldap://keys.(thedomain)'.


              keyserver
                     Locate a key using whatever keyserver is defined using the --keyserver option.


              keyserver-URL
                     In  addition,  a  keyserver  URL as used in the --keyserver option may be used here to query that
                     particular keyserver.


              local  Locate the key using the local keyrings.  This mechanism allows to select the order a  local  key
                     lookup is done.  Thus using '--auto-key-locate local' is identical to --no-auto-key-locate.


              nodefault
                     This  flag  disables  the standard local key lookup, done before any of the mechanisms defined by
                     the --auto-key-locate are tried.  The position of this mechanism in the list does not matter.  It
                     is not required if local is also used.



       --keyid-format short|0xshort|long|0xlong
              Select  how  to display key IDs. "short" is the traditional 8-character key ID. "long" is the more accu-
              rate (but less convenient) 16-character key ID. Add an "0x" to either to include an "0x" at  the  begin-
              ning of the key ID, as in 0x99242560.


       --keyserver name
              Use  name  as  your  keyserver. This is the server that --recv-keys, --send-keys, and --search-keys will
              communicate with to receive keys from, send keys to, and search for keys on. The format of the name is a
              URI:  'scheme:[//]keyservername[:port]' The scheme is the type of keyserver: "hkp" for the HTTP (or com-
              patible) keyservers, "ldap" for the LDAP keyservers, or "mailto" for the  Graff  email  keyserver.  Note
              that  your  particular installation of GnuPG may have other keyserver types available as well. Keyserver
              schemes are case-insensitive. After the keyserver name, optional keyserver configuration options may  be
              provided.  These  are the same as the global --keyserver-options from below, but apply only to this par-
              ticular keyserver.

              Most keyservers synchronize with each other, so there is generally no need to send keys to more than one
              server.  The keyserver hkp://keys.gnupg.net uses round robin DNS to give a different keyserver each time
              you use it.


       --keyserver-options name=value1
              This is a space or comma delimited string that gives options for the keyserver. Options can be  prefixed
              with  a  'no-'  to give the opposite meaning. Valid import-options or export-options may be used here as
              well to apply to importing (--recv-key) or exporting (--send-key) a key from a keyserver. While not  all
              options are available for all keyserver types, some common options are:



              include-revoked
                     When  searching  for  a  key with --search-keys, include keys that are marked on the keyserver as
                     revoked. Note that not all keyservers differentiate between revoked and unrevoked keys,  and  for
                     such  keyservers  this  option is meaningless. Note also that most keyservers do not have crypto-
                     graphic verification of key revocations, and so turning this option off may  result  in  skipping
                     keys that are incorrectly marked as revoked.


              include-disabled
                     When  searching  for  a  key with --search-keys, include keys that are marked on the keyserver as
                     disabled. Note that this option is not used with HKP keyservers.


              auto-key-retrieve
                     This option enables the automatic retrieving of keys from a keyserver when  verifying  signatures
                     made by keys that are not on the local keyring.

                     Note  that  this  option  makes  a "web bug" like behavior possible.  Keyserver operators can see
                     which keys you request, so by sending you a message signed by a brand new key  (which  you  natu-
                     rally  will  not  have on your local keyring), the operator can tell both your IP address and the
                     time when you verified the signature.


              honor-keyserver-url
                     When using --refresh-keys, if the key in question has a preferred keyserver URL,  then  use  that
                     preferred  keyserver  to  refresh the key from. In addition, if auto-key-retrieve is set, and the
                     signature being verified has a preferred keyserver URL, then  use  that  preferred  keyserver  to
                     fetch the key from. Defaults to yes.


              honor-pka-record
                     If  auto-key-retrieve is set, and the signature being verified has a PKA record, then use the PKA
                     information to fetch the key. Defaults to yes.


              include-subkeys
                     When receiving a key, include subkeys as potential targets. Note that this  option  is  not  used
                     with HKP keyservers, as they do not support retrieving keys by subkey id.


              use-temp-files
                     On  most  Unix-like  platforms,  GnuPG  communicates with the keyserver helper program via pipes,
                     which is the most efficient method. This option forces GnuPG to use temporary files  to  communi-
                     cate. On some platforms (such as Win32 and RISC OS), this option is always enabled.


              keep-temp-files
                     If  using  'use-temp-files', do not delete the temp files after using them. This option is useful
                     to learn the keyserver communication protocol by reading the temporary files.


              verbose
                     Tell the keyserver helper program to be more verbose. This option can be repeated multiple  times
                     to increase the verbosity level.


              timeout
                     Tell  the  keyserver  helper  program how long (in seconds) to try and perform a keyserver action
                     before giving up. Note that performing multiple actions at the same time uses this timeout  value
                     per action.  For example, when retrieving multiple keys via --recv-keys, the timeout applies sep-
                     arately to each key retrieval, and not to the --recv-keys command as a whole. Defaults to 30 sec-
                     onds.


              http-proxy=value
                     Set  the  proxy  to use for HTTP and HKP keyservers.  This overrides the "http_proxy" environment
                     variable, if any.


              max-cert-size
                     When retrieving a key via DNS CERT, only accept keys up to this size.  Defaults to 16384 bytes.


              debug  Turn on debug output in the keyserver helper program.  Note that  the  details  of  debug  output
                     depends  on  which keyserver helper program is being used, and in turn, on any libraries that the
                     keyserver helper program uses internally (libcurl, openldap, etc).


              check-cert
                     Enable certificate checking if the keyserver presents one (for hkps or ldaps).  Defaults to on.


              ca-cert-file
                     Provide a certificate file to override the system  default.   Only  necessary  if  check-cert  is
                     enabled,  and  the  keyserver is using a certificate that is not present in a system default cer-
                     tificate list.



       --completes-needed n
              Number of completely trusted users to introduce a new key signer (defaults to 1).


       --marginals-needed n
              Number of marginally trusted users to introduce a new key signer (defaults to 3)


       --max-cert-depth n
              Maximum depth of a certification chain (default is 5).


       --simple-sk-checksum
              Secret keys are integrity protected by using a SHA-1 checksum. This  method  is  part  of  the  upcoming
              enhanced  OpenPGP  specification  but GnuPG already uses it as a countermeasure against certain attacks.
              Old applications don't understand this new format, so this option may be used to switch back to the  old
              behaviour.  Using  this option bears a security risk. Note that using this option only takes effect when
              the secret key is encrypted - the simplest way to make this happen is to change the  passphrase  on  the
              key (even changing it to the same value is acceptable).


       --no-sig-cache
              Do  not cache the verification status of key signatures.  Caching gives a much better performance in key
              listings. However, if you suspect that your public keyring is not save against write modifications,  you
              can  use  this  option to disable the caching. It probably does not make sense to disable it because all
              kind of damage can be done if someone else has write access to your public keyring.


       --no-sig-create-check
              GnuPG normally verifies each signature right after creation to protect against bugs  and  hardware  mal-
              functions  which could leak out bits from the secret key. This extra verification needs some time (about
              115% for DSA keys), and so this option can be used to disable it.  However, due to  the  fact  that  the
              signature  creation needs manual interaction, this performance penalty does not matter in most settings.


       --auto-check-trustdb

       --no-auto-check-trustdb
              If GnuPG feels that its information about the Web of Trust has to be updated, it automatically runs  the
              --check-trustdb  command internally.  This may be a time consuming process. --no-auto-check-trustdb dis-
              ables this option.


       --use-agent

       --no-use-agent
              This is dummy option. gpg2 always requires the agent.


       --gpg-agent-info
              This is dummy option. It has no effect when used with gpg2.


       --lock-once
              Lock the databases the first time a lock is requested and do not release the lock until the process ter-
              minates.


       --lock-multiple
              Release  the  locks  every  time a lock is no longer needed. Use this to override a previous --lock-once
              from a config file.


       --lock-never
              Disable locking entirely. This option should be used only in very special environments, where it can  be
              assured  that only one process is accessing those files. A bootable floppy with a stand-alone encryption
              system will probably use this. Improper usage of this option may lead to data and key corruption.


       --exit-on-status-write-error
              This option will cause write errors on the status FD to immediately terminate the process.  That  should
              in  fact  be the default but it never worked this way and thus we need an option to enable this, so that
              the change won't break applications which close their end of a status fd connected pipe too early. Using
              this  option  along  with --enable-progress-filter may be used to cleanly cancel long running gpg opera-
              tions.


       --limit-card-insert-tries n
              With n greater than 0 the number of prompts asking to insert a smartcard gets limited to N-1. Thus  with
              a  value of 1 gpg won't at all ask to insert a card if none has been inserted at startup. This option is
              useful in the configuration file in case an application does not know about the  smartcard  support  and
              waits ad infinitum for an inserted card.


       --no-random-seed-file
              GnuPG  uses  a  file  to  store its internal random pool over invocations.  This makes random generation
              faster; however sometimes write operations are not desired. This option can be used to achieve that with
              the cost of slower random generation.


       --no-greeting
              Suppress the initial copyright message.


       --no-secmem-warning
              Suppress the warning about "using insecure memory".


       --no-permission-warning
              Suppress the warning about unsafe file and home directory (--homedir) permissions. Note that the permis-
              sion checks that GnuPG performs are not intended to be authoritative, but rather they simply warn  about
              certain  common  permission problems. Do not assume that the lack of a warning means that your system is
              secure.

              Note that the warning for unsafe --homedir permissions cannot be suppressed in  the  gpg.conf  file,  as
              this  would  allow  an attacker to place an unsafe gpg.conf file in place, and use this file to suppress
              warnings about itself. The --homedir permissions warning may only be suppressed on the command line.


       --no-mdc-warning
              Suppress the warning about missing MDC integrity protection.


       --require-secmem

       --no-require-secmem
              Refuse to run if GnuPG cannot get secure memory. Defaults to no (i.e. run, but give a warning).



       --require-cross-certification

       --no-require-cross-certification
              When verifying a signature made from a subkey, ensure that the cross certification "back  signature"  on
              the  subkey  is present and valid.  This protects against a subtle attack against subkeys that can sign.
              Defaults to --require-cross-certification for gpg2.


       --expert

       --no-expert
              Allow the user to do certain nonsensical or "silly" things like signing an expired or  revoked  key,  or
              certain  potentially  incompatible  things like generating unusual key types. This also disables certain
              warning messages about potentially incompatible actions. As the name implies, this option is for experts
              only.  If you don't fully understand the implications of what it allows you to do, leave this off. --no-
              expert disables this option.








   Key related options




       --recipient name

       -r     Encrypt for user id name. If this option or --hidden-recipient is not  specified,  GnuPG  asks  for  the
              user-id unless --default-recipient is given.


       --hidden-recipient name

       -R     Encrypt for user ID name, but hide the key ID of this user's key. This option helps to hide the receiver
              of the message and is a limited countermeasure against traffic analysis. If this option  or  --recipient
              is not specified, GnuPG asks for the user ID unless --default-recipient is given.


       --encrypt-to name
              Same  as  --recipient but this one is intended for use in the options file and may be used with your own
              user-id as an "encrypt-to-self". These keys are only used when there are other recipients  given  either
              by  use  of  --recipient or by the asked user id.  No trust checking is performed for these user ids and
              even disabled keys can be used.


       --hidden-encrypt-to name
              Same as --hidden-recipient but this one is intended for use in the options file and  may  be  used  with
              your own user-id as a hidden "encrypt-to-self". These keys are only used when there are other recipients
              given either by use of --recipient or by the asked user id.  No trust checking is  performed  for  these
              user ids and even disabled keys can be used.


       --no-encrypt-to
              Disable the use of all --encrypt-to and --hidden-encrypt-to keys.


       --group name=value1
              Sets  up  a  named  group,  which is similar to aliases in email programs.  Any time the group name is a
              recipient (-r or --recipient), it will be expanded to the values specified.  Multiple  groups  with  the
              same name are automatically merged into a single group.

              The  values  are  key  IDs  or fingerprints, but any key description is accepted. Note that a value with
              spaces in it will be treated as two different values. Note also there is only one level of expansion ---
              you cannot make an group that points to another group. When used from the command line, it may be neces-
              sary to quote the argument to this option to prevent the shell from treating it as multiple arguments.


       --ungroup name
              Remove a given entry from the --group list.


       --no-groups
              Remove all entries from the --group list.


       --local-user name

       -u     Use name as the key to sign with. Note that this option overrides --default-key.


       --try-all-secrets
              Don't look at the key ID as stored in the message but try all secret keys in  turn  to  find  the  right
              decryption  key.  This  option  forces  the  behaviour as used by anonymous recipients (created by using
              --throw-keyids) and might come handy in case where an encrypted message contains a bogus key ID.








   Input and Output




       --armor

       -a     Create ASCII armored output.  The default is to create the binary OpenPGP format.


       --no-armor
              Assume the input data is not in ASCII armored format.


       --output file

       -o file
              Write output to file.


       --max-output n
              This option sets a limit on the number of bytes that will be generated when  processing  a  file.  Since
              OpenPGP supports various levels of compression, it is possible that the plaintext of a given message may
              be significantly larger than the original OpenPGP message. While GnuPG works  properly  with  such  mes-
              sages,  there  is  often a desire to set a maximum file size that will be generated before processing is
              forced to stop by the OS limits. Defaults to 0, which means "no limit".


       --import-options parameters
              This is a space or comma delimited string  that  gives  options  for  importing  keys.  Options  can  be
              prepended with a 'no-' to give the opposite meaning. The options are:



              import-local-sigs
                     Allow  importing  key  signatures marked as "local". This is not generally useful unless a shared
                     keyring scheme is being used.  Defaults to no.


              repair-pks-subkey-bug
                     During import, attempt to repair the damage caused by the PKS keyserver bug (pre  version  0.9.6)
                     that  mangles keys with multiple subkeys. Note that this cannot completely repair the damaged key
                     as some crucial data is removed by the keyserver, but it does at least give you back one  subkey.
                     Defaults to no for regular --import and to yes for keyserver --recv-keys.


              merge-only
                     During  import, allow key updates to existing keys, but do not allow any new keys to be imported.
                     Defaults to no.


              import-clean
                     After import, compact (remove all signatures except the self-signature) any user IDs from the new
                     key that are not usable.  Then, remove any signatures from the new key that are not usable.  This
                     includes signatures that were issued by keys that are not present on the keyring. This option  is
                     the same as running the --edit-key command "clean" after import. Defaults to no.


              import-minimal
                     Import  the smallest key possible. This removes all signatures except the most recent self-signa-
                     ture on each user ID. This option is the same as running the --edit-key command "minimize"  after
                     import.  Defaults to no.


       --export-options parameters
              This  is  a  space  or  comma  delimited  string  that  gives options for exporting keys. Options can be
              prepended with a 'no-' to give the opposite meaning. The options are:



              export-local-sigs
                     Allow exporting key signatures marked as "local". This is not generally useful  unless  a  shared
                     keyring scheme is being used.  Defaults to no.


              export-attributes
                     Include attribute user IDs (photo IDs) while exporting. This is useful to export keys if they are
                     going to be used by an OpenPGP program that does not accept attribute user IDs. Defaults to  yes.


              export-sensitive-revkeys
                     Include designated revoker information that was marked as "sensitive". Defaults to no.


              export-reset-subkey-passwd
                     When  using  the  --export-secret-subkeys  command,  this  option  resets the passphrases for all
                     exported subkeys to empty. This is useful when the exported subkey is to be used on an unattended
                     machine where a passphrase doesn't necessarily make sense. Defaults to no.


              export-clean
                     Compact  (remove  all signatures from) user IDs on the key being exported if the user IDs are not
                     usable. Also, do not export any signatures that are not usable.  This  includes  signatures  that
                     were  issued  by keys that are not present on the keyring. This option is the same as running the
                     --edit-key command "clean" before export except that the local copy of the key is  not  modified.
                     Defaults to no.


              export-minimal
                     Export  the smallest key possible. This removes all signatures except the most recent self-signa-
                     ture on each user ID. This option is the same as running the --edit-key command "minimize" before
                     export except that the local copy of the key is not modified. Defaults to no.


       --with-colons
              Print  key listings delimited by colons. Note that the output will be encoded in UTF-8 regardless of any
              --display-charset setting. This format is useful when GnuPG is called from scripts and other programs as
              it  is easily machine parsed. The details of this format are documented in the file 'doc/DETAILS', which
              is included in the GnuPG source distribution.


       --fixed-list-mode
              Do not merge primary user ID and primary key in --with-colon listing mode and print  all  timestamps  as
              seconds  since  1970-01-01.   Since GnuPG 2.0.10, this mode is always used and thus this option is obso-
              lete; it does not harm to use it though.


       --with-fingerprint
              Same as the command --fingerprint but changes only the format of the output and  may  be  used  together
              with another command.





   OpenPGP protocol specific options.




       -t, --textmode

       --no-textmode
              Treat  input  files  as text and store them in the OpenPGP canonical text form with standard "CRLF" line
              endings. This also sets the necessary flags to inform the recipient that the encrypted or signed data is
              text and may need its line endings converted back to whatever the local system uses. This option is use-
              ful when communicating between two platforms that have different line ending conventions  (UNIX-like  to
              Mac, Mac to Windows, etc). --no-textmode disables this option, and is the default.



       --force-v3-sigs

       --no-force-v3-sigs
              OpenPGP  states  that  an implementation should generate v4 signatures but PGP versions 5 through 7 only
              recognize v4 signatures on key material. This option forces v3 signatures for signatures on data.   Note
              that this option implies --ask-sig-expire, --sig-policy-url, --sig-notation, and --sig-keyserver-url, as
              these features cannot be used with v3 signatures.  --no-force-v3-sigs disables this option.


       --force-v4-certs

       --no-force-v4-certs
              Always use v4 key signatures even on v3 keys. This option also changes the default hash algorithm for v3
              RSA keys from MD5 to SHA-1.  --no-force-v4-certs disables this option.


       --force-mdc
              Force  the  use  of  encryption  with  a modification detection code. This is always used with the newer
              ciphers (those with a blocksize greater than 64 bits), or if all of the recipient keys indicate MDC sup-
              port in their feature flags.


       --disable-mdc
              Disable  the  use of the modification detection code. Note that by using this option, the encrypted mes-
              sage becomes vulnerable to a message modification attack.


       --personal-cipher-preferences string
              Set the list of personal cipher preferences to string.  Use gpg2 --version to get a  list  of  available
              algorithms, and use none to set no preference at all.  This allows the user to safely override the algo-
              rithm chosen by the recipient key preferences, as GPG will only select an algorithm that  is  usable  by
              all  recipients.  The most highly ranked cipher in this list is also used for the --symmetric encryption
              command.


       --personal-digest-preferences string
              Set the list of personal digest preferences to string.  Use gpg2 --version to get a  list  of  available
              algorithms, and use none to set no preference at all.  This allows the user to safely override the algo-
              rithm chosen by the recipient key preferences, as GPG will only select an algorithm that  is  usable  by
              all  recipients.  The most highly ranked digest algorithm in this list is also used when signing without
              encryption (e.g. --clearsign or --sign). The default value is SHA-1.


       --personal-compress-preferences string
              Set the list of personal compression preferences to string.  Use gpg2 --version to get a list of  avail-
              able  algorithms, and use none to set no preference at all.  This allows the user to safely override the
              algorithm chosen by the recipient key preferences, as GPG will only select an algorithm that  is  usable
              by  all  recipients.   The most highly ranked compression algorithm in this list is also used when there
              are no recipient keys to consider (e.g. --symmetric).


       --s2k-cipher-algo name
              Use name as the cipher algorithm used to protect secret keys.  The default cipher is CAST5. This  cipher
              is  also  used  for  conventional  encryption  if --personal-cipher-preferences and --cipher-algo is not
              given.


       --s2k-digest-algo name
              Use name as the digest algorithm used to mangle the passphrases.  The default algorithm is SHA-1.


       --s2k-mode n
              Selects how passphrases are mangled. If n is 0 a plain passphrase (which is  not  recommended)  will  be
              used,  a  1  adds  a salt to the passphrase and a 3 (the default) iterates the whole process a number of
              times (see --s2k-count).  Unless --rfc1991 is used, this mode is also used for conventional  encryption.


       --s2k-count n
              Specify  how  many  times  the  passphrase  mangling is repeated.  This value may range between 1024 and
              65011712 inclusive, and the default is 65536.  Note that not all values in the 1024-65011712  range  are
              legal  and if an illegal value is selected, GnuPG will round up to the nearest legal value.  This option
              is only meaningful if --s2k-mode is 3.





   Compliance options


       These options control what GnuPG is compliant to. Only one of these options may be active at a time. Note  that
       the  default setting of this is nearly always the correct one. See the INTEROPERABILITY WITH OTHER OPENPGP PRO-
       GRAMS section below before using one of these options.



       --gnupg
              Use standard GnuPG behavior. This is essentially OpenPGP behavior (see --openpgp), but with  some  addi-
              tional  workarounds  for common compatibility problems in different versions of PGP. This is the default
              option, so it is not generally needed, but it may be useful to override a different compliance option in
              the gpg.conf file.


       --openpgp
              Reset  all  packet,  cipher  and digest options to strict OpenPGP behavior. Use this option to reset all
              previous options like --s2k-*, --cipher-algo, --digest-algo and  --compress-algo  to  OpenPGP  compliant
              values. All PGP workarounds are disabled.


       --rfc4880
              Reset all packet, cipher and digest options to strict RFC-4880 behavior. Note that this is currently the
              same thing as --openpgp.


       --rfc2440
              Reset all packet, cipher and digest options to strict RFC-2440 behavior.


       --rfc1991
              Try to be more RFC-1991 (PGP 2.x) compliant.


       --pgp2 Set up all options to be as PGP 2.x compliant as possible, and warn if an action is taken (e.g. encrypt-
              ing to a non-RSA key) that will create a message that PGP 2.x will not be able to handle. Note that 'PGP
              2.x' here means 'MIT PGP 2.6.2'. There are other versions of PGP 2.x available, but the MIT release is a
              good common baseline.

              This  option  implies  --rfc1991  --disable-mdc  --no-force-v4-certs --escape-from-lines --force-v3-sigs
              --cipher-algo IDEA --digest-algo MD5 --compress-algo ZIP. It also disables --textmode when encrypting.


       --pgp6 Set up all options to be as PGP 6 compliant as possible. This restricts you to the ciphers IDEA (if  the
              IDEA  plugin  is  installed),  3DES,  and CAST5, the hashes MD5, SHA1 and RIPEMD160, and the compression
              algorithms none and ZIP. This also disables --throw-keyids, and making signatures with  signing  subkeys
              as PGP 6 does not understand signatures made by signing subkeys.

              This option implies --disable-mdc --escape-from-lines --force-v3-sigs.


       --pgp7 Set  up  all  options to be as PGP 7 compliant as possible. This is identical to --pgp6 except that MDCs
              are not disabled, and the list of allowable ciphers is expanded  to  add  AES128,  AES192,  AES256,  and
              TWOFISH.


       --pgp8 Set  up  all options to be as PGP 8 compliant as possible. PGP 8 is a lot closer to the OpenPGP standard
              than previous versions of PGP, so all this does is disable --throw-keyids and  set  --escape-from-lines.
              All algorithms are allowed except for the SHA224, SHA384, and SHA512 digests.





   Doing things one usually doesn't want to do.




       -n

       --dry-run
              Don't make any changes (this is not completely implemented).


       --list-only
              Changes the behaviour of some commands. This is like --dry-run but different in some cases. The semantic
              of this command may be extended in the future. Currently it only skips the actual  decryption  pass  and
              therefore enables a fast listing of the encryption keys.


       -i

       --interactive
              Prompt before overwriting any files.


       --debug-level level
              Select the debug level for investigating problems. level may be a numeric value or by a keyword:


              none   No debugging at all.  A value of less than 1 may be used instead of the keyword.

              basic  Some basic debug messages.  A value between 1 and 2 may be used instead of the keyword.

              advanced
                     More verbose debug messages.  A value between 3 and 5 may be used instead of the keyword.

              expert Even more detailed messages.  A value between 6 and 8 may be used instead of the keyword.

              guru   All of the debug messages you can get. A value greater than 8 may be used instead of the keyword.
                     The creation of hash tracing files is only enabled if the keyword is used.

       How these messages are mapped to the actual debugging flags is not specified and may change with newer releases
       of this program. They are however carefully selected to best aid in debugging.


       --debug flags
              Set debugging flags. All flags are or-ed and flags may be given in C syntax (e.g. 0x0042).


       --debug-all
              Set all useful debugging flags.



       --enable-progress-filter
              Enable  certain  PROGRESS  status  outputs. This option allows frontends to display a progress indicator
              while gpg is processing larger files.  There is a slight performance overhead using it.


       --status-fd n
              Write special status strings to the file descriptor n.  See the file DETAILS in the documentation for  a
              listing of them.


       --status-file file
              Same as --status-fd, except the status data is written to file file.


       --logger-fd n
              Write log output to file descriptor n and not to STDERR.


       --log-file file

       --logger-file file
              Same  as  --logger-fd,  except  the  logger  data is written to file file.  Note that --log-file is only
              implemented for GnuPG-2.


       --attribute-fd n
              Write attribute subpackets to the file descriptor n. This is most useful for use with --status-fd, since
              the  status  messages are needed to separate out the various subpackets from the stream delivered to the
              file descriptor.


       --attribute-file file
              Same as --attribute-fd, except the attribute data is written to file file.


       --comment string

       --no-comments
              Use string as a comment string in clear  text  signatures  and  ASCII  armored  messages  or  keys  (see
              --armor).  The default behavior is not to use a comment string. --comment may be repeated multiple times
              to get multiple comment strings. --no-comments removes all comments.  It is a  good  idea  to  keep  the
              length of a single comment below 60 characters to avoid problems with mail programs wrapping such lines.
              Note that comment lines, like all other header lines, are not protected by the signature.


       --emit-version

       --no-emit-version
              Force inclusion of the version string in ASCII armored output.  --no-emit-version disables this  option.


       --sig-notation name=value

       --cert-notation name=value

       -N, --set-notation name=value
              Put  the name value pair into the signature as notation data.  name must consist only of printable char-
              acters or spaces, and must contain a '@' character in the form keynameATdomain.com  (substituting
              the  appropriate  keyname  and  domain  name, of course).  This is to help prevent pollution of the IETF
              reserved notation namespace. The --expert flag overrides the '@'  check.  value  may  be  any  printable
              string; it will be encoded in UTF8, so you should check that your --display-charset is set correctly. If
              you prefix name  with  an  exclamation  mark  (!),  the  notation  data  will  be  flagged  as  critical
              (rfc2440:5.2.3.15).  --sig-notation sets a notation for data signatures. --cert-notation sets a notation
              for key signatures (certifications). --set-notation sets both.

              There are special codes that may be used in notation names. "%k" will be expanded into the key ID of the
              key  being  signed,  "%K" into the long key ID of the key being signed, "%f" into the fingerprint of the
              key being signed, "%s" into the key ID of the key making the signature, "%S" into the long key ID of the
              key  making  the  signature, "%g" into the fingerprint of the key making the signature (which might be a
              subkey), "%p" into the fingerprint of the primary key of the key making the  signature,  "%c"  into  the
              signature  count  from  the OpenPGP smartcard, and "%%" results in a single "%". %k, %K, and %f are only
              meaningful when making a key signature (certification), and %c is only meaningful when using the OpenPGP
              smartcard.


       --sig-policy-url string

       --cert-policy-url string

       --set-policy-url string
              Use string as a Policy URL for signatures (rfc2440:5.2.3.19).  If you prefix it with an exclamation mark
              (!), the policy URL packet will be flagged as critical. --sig-policy-url sets a policy url for data sig-
              natures.  --cert-policy-url sets a policy url for key signatures (certifications). --set-policy-url sets
              both.

              The same %-expandos used for notation data are available here as well.


       --sig-keyserver-url string
              Use string as a preferred keyserver URL for data signatures. If you prefix it with an  exclamation  mark
              (!), the keyserver URL packet will be flagged as critical.

              The same %-expandos used for notation data are available here as well.


       --set-filename string
              Use string as the filename which is stored inside messages.  This overrides the default, which is to use
              the actual filename of the file being encrypted.


       --for-your-eyes-only

       --no-for-your-eyes-only
              Set the 'for your eyes only' flag in the message. This causes GnuPG to refuse to save  the  file  unless
              the  --output option is given, and PGP to use a "secure viewer" with a claimed Tempest-resistant font to
              display the message.  This  option  overrides  --set-filename.   --no-for-your-eyes-only  disables  this
              option.


       --use-embedded-filename

       --no-use-embedded-filename
              Try to create a file with a name as embedded in the data. This can be a dangerous option as it allows to
              overwrite files. Defaults to no.


       --cipher-algo name
              Use name as cipher algorithm. Running the program with the command --version yields a list of  supported
              algorithms.  If  this  is not used the cipher algorithm is selected from the preferences stored with the
              key. In general, you do not want to use this option as it allows you to violate  the  OpenPGP  standard.
              --personal-cipher-preferences is the safe way to accomplish the same thing.


       --digest-algo name
              Use  name  as the message digest algorithm. Running the program with the command --version yields a list
              of supported algorithms. In general, you do not want to use this option as it allows you to violate  the
              OpenPGP standard. --personal-digest-preferences is the safe way to accomplish the same thing.


       --compress-algo name
              Use  compression  algorithm name. "zlib" is RFC-1950 ZLIB compression. "zip" is RFC-1951 ZIP compression
              which is used by PGP.  "bzip2" is a more modern compression scheme that can compress some things  better
              than  zip  or  zlib,  but  at the cost of more memory used during compression and decompression. "uncom-
              pressed" or "none" disables compression. If this option is not used, the default behavior is to  examine
              the  recipient key preferences to see which algorithms the recipient supports. If all else fails, ZIP is
              used for maximum compatibility.

              ZLIB may give better compression results than ZIP, as the compression window size is not limited to  8k.
              BZIP2  may give even better compression results than that, but will use a significantly larger amount of
              memory while compressing and decompressing. This may be significant in low memory situations. Note, how-
              ever,  that  PGP  (all  versions)  only  supports ZIP compression. Using any algorithm other than ZIP or
              "none" will make the message unreadable with PGP. In general, you do not want to use this option  as  it
              allows  you  to  violate the OpenPGP standard. --personal-compress-preferences is the safe way to accom-
              plish the same thing.


       --cert-digest-algo name
              Use name as the message digest algorithm used when signing a key. Running the program with  the  command
              --version  yields  a  list  of supported algorithms. Be aware that if you choose an algorithm that GnuPG
              supports but other OpenPGP implementations do not, then some users will not be able to use the key  sig-
              natures you make, or quite possibly your entire key.


       --disable-cipher-algo name
              Never  allow  the  use  of name as cipher algorithm.  The given name will not be checked so that a later
              loaded algorithm will still get disabled.


       --disable-pubkey-algo name
              Never allow the use of name as public key algorithm.  The given name will not be checked so that a later
              loaded algorithm will still get disabled.


       --throw-keyids

       --no-throw-keyids
              Do  not  put the recipient key IDs into encrypted messages. This helps to hide the receivers of the mes-
              sage and is a limited countermeasure against traffic analysis. ([Using a little social engineering  any-
              one  who is able to decrypt the message can check whether one of the other recipients is the one he sus-
              pects.])  On the receiving side, it may slow down the decryption process because  all  available  secret
              keys  must  be  tried.   --no-throw-keyids  disables this option. This option is essentially the same as
              using --hidden-recipient for all recipients.


       --not-dash-escaped
              This option changes the behavior of cleartext signatures so that they can be used for patch  files.  You
              should  not  send such an armored file via email because all spaces and line endings are hashed too. You
              can not use this option for data which has 5 dashes at the beginning of a line, patch files  don't  have
              this. A special armor header line tells GnuPG about this cleartext signature option.


       --escape-from-lines

       --no-escape-from-lines
              Because some mailers change lines starting with "From " to ">From " it is good to handle such lines in a
              special way when creating cleartext signatures to prevent the mail system from breaking  the  signature.
              Note  that  all  other PGP versions do it this way too.  Enabled by default. --no-escape-from-lines dis-
              ables this option.


       --passphrase-repeat n
              Specify how many times gpg2 will request a new passphrase be repeated.  This is useful for helping memo-
              rize a passphrase.  Defaults to 1 repetition.


       --passphrase-fd n
              Read  the passphrase from file descriptor n. Only the first line will be read from file descriptor n. If
              you use 0 for n, the passphrase will be read from STDIN. This can only be used if only one passphrase is
              supplied.   Note  that  this passphrase is only used if the option --batch has also been given.  This is
              different from gpg.


       --passphrase-file file
              Read the passphrase from file file. Only the first line will be read from file file. This  can  only  be
              used  if  only  one  passphrase is supplied. Obviously, a passphrase stored in a file is of questionable
              security if other users can read this file. Don't use this option if you can avoid it.  Note  that  this
              passphrase is only used if the option --batch has also been given.  This is different from gpg.


       --passphrase string
              Use  string as the passphrase. This can only be used if only one passphrase is supplied. Obviously, this
              is of very questionable security on a multi-user system. Don't use this option  if  you  can  avoid  it.
              Note  that  this  passphrase  is only used if the option --batch has also been given.  This is different
              from gpg.


       --command-fd n
              This is a replacement for the deprecated shared-memory IPC mode.  If this option is enabled, user  input
              on questions is not expected from the TTY but from the given file descriptor. It should be used together
              with --status-fd. See the file doc/DETAILS in the source distribution for details on how to use it.


       --command-file file
              Same as --command-fd, except the commands are read out of file file


       --allow-non-selfsigned-uid

       --no-allow-non-selfsigned-uid
              Allow the import and use of keys with user IDs which are not self-signed. This is not recommended, as  a
              non self-signed user ID is trivial to forge. --no-allow-non-selfsigned-uid disables.


       --allow-freeform-uid
              Disable  all  checks  on  the form of the user ID while generating a new one. This option should only be
              used in very special environments as it does not ensure the de-facto standard format of user IDs.


       --ignore-time-conflict
              GnuPG normally checks that the timestamps associated with keys and  signatures  have  plausible  values.
              However,  sometimes  a signature seems to be older than the key due to clock problems. This option makes
              these checks just a warning. See also --ignore-valid-from for timestamp issues on subkeys.


       --ignore-valid-from
              GnuPG normally does not select and use subkeys created in the future.  This option  allows  the  use  of
              such  keys and thus exhibits the pre-1.0.7 behaviour. You should not use this option unless you there is
              some clock problem. See also --ignore-time-conflict for timestamp issues with signatures.


       --ignore-crc-error
              The ASCII armor used by OpenPGP is protected by a CRC checksum against transmission errors. Occasionally
              the CRC gets mangled somewhere on the transmission channel but the actual content (which is protected by
              the OpenPGP protocol anyway) is still okay. This option allows GnuPG to ignore CRC errors.


       --ignore-mdc-error
              This option changes a MDC integrity protection failure into a warning.  This can be useful if a  message
              is  partially  corrupt,  but it is necessary to get as much data as possible out of the corrupt message.
              However, be aware that a MDC protection failure may also mean that the message was tampered with  inten-
              tionally by an attacker.


       --no-default-keyring
              Do  not  add  the default keyrings to the list of keyrings. Note that GnuPG will not operate without any
              keyrings, so if you use this option and do not provide alternate keyrings  via  --keyring  or  --secret-
              keyring, then GnuPG will still use the default public or secret keyrings.


       --skip-verify
              Skip  the  signature  verification step. This may be used to make the decryption faster if the signature
              verification is not needed.


       --with-key-data
              Print key listings delimited by colons (like --with-colons) and print the public key data.


       --fast-list-mode
              Changes the output of the list commands to work faster; this is achieved by leaving  some  parts  empty.
              Some  applications don't need the user ID and the trust information given in the listings. By using this
              options they can get a faster listing. The exact behaviour of this option may change in future versions.
              If you are missing some information, don't use this option.


       --no-literal
              This is not for normal use. Use the source to see for what it might be useful.


       --set-filesize
              This is not for normal use. Use the source to see for what it might be useful.


       --show-session-key
              Display  the  session  key  used for one message. See --override-session-key for the counterpart of this
              option.

              We think that Key Escrow is a Bad Thing; however the user should have the freedom to decide  whether  to
              go  to  prison  or  to reveal the content of one specific message without compromising all messages ever
              encrypted for one secret key. DON'T USE IT UNLESS YOU ARE REALLY FORCED TO DO SO.


       --override-session-key string
              Don't use the public key but the session key string. The format of this string is the same  as  the  one
              printed  by  --show-session-key. This option is normally not used but comes handy in case someone forces
              you to reveal the content of an encrypted message; using this option you can do this without handing out
              the secret key.


       --ask-sig-expire

       --no-ask-sig-expire
              When  making a data signature, prompt for an expiration time. If this option is not specified, the expi-
              ration time set via --default-sig-expire is used. --no-ask-sig-expire disables this option. Note that by
              default,  --force-v3-sigs  is set which also disables this option. If you want signature expiration, you
              must set --no-force-v3-sigs as well as turning --ask-sig-expire on.


       --default-sig-expire
              The default expiration time to use for signature expiration. Valid values are "0" for no  expiration,  a
              number followed by the letter d (for days), w (for weeks), m (for months), or y (for years) (for example
              "2m" for two months, or "5y" for five years), or an absolute date in the form  YYYY-MM-DD.  Defaults  to
              "0".


       --ask-cert-expire

       --no-ask-cert-expire
              When making a key signature, prompt for an expiration time. If this option is not specified, the expira-
              tion time set via --default-cert-expire is used. --no-ask-cert-expire disables this option.


       --default-cert-expire
              The default expiration time to use for key signature expiration.  Valid values are "0"  for  no  expira-
              tion, a number followed by the letter d (for days), w (for weeks), m (for months), or y (for years) (for
              example "2m" for two months, or "5y" for five years), or  an  absolute  date  in  the  form  YYYY-MM-DD.
              Defaults to "0".


       --allow-secret-key-import
              This is an obsolete option and is not used anywhere.


       --allow-multiple-messages

       --no-allow-multiple-messages
              Allow  processing of multiple OpenPGP messages contained in a single file or stream.  Some programs that
              call GPG are not prepared to deal with multiple  messages  being  processed  together,  so  this  option
              defaults to no.  Note that versions of GPG prior to 1.4.7 always allowed multiple messages.

              Warning: Do not use this option unless you need it as a temporary workaround!



       --enable-special-filenames
              This options enables a mode in which filenames of the form '-&n', where n is a non-negative decimal num-
              ber, refer to the file descriptor n and not to a file with that name.


       --no-expensive-trust-checks
              Experimental use only.


       --preserve-permissions
              Don't change the permissions of a secret keyring back to user read/write only. Use this option  only  if
              you really know what you are doing.


       --default-preference-list string
              Set the list of default preferences to string. This preference list is used for new keys and becomes the
              default for "setpref" in the edit menu.


       --default-keyserver-url name
              Set the default keyserver URL to name. This keyserver will be used as the keyserver URL when  writing  a
              new self-signature on a key, which includes key generation and changing preferences.


       --list-config
              Display  various  internal  configuration parameters of GnuPG. This option is intended for external pro-
              grams that call GnuPG to perform tasks, and is thus not generally useful. See the file 'doc/DETAILS'  in
              the  source  distribution  for  the details of which configuration items may be listed. --list-config is
              only usable with --with-colons set.


       --gpgconf-list
              This command is similar to --list-config but in general only internally used by the gpgconf tool.


       --gpgconf-test
              This is more or less dummy action.  However it parses the configuration file and returns with failure if
              the configuration file would prevent gpg from startup.  Thus it may be used to run a syntax check on the
              configuration file.




   Deprecated options





       --show-photos

       --no-show-photos
              Causes --list-keys, --list-sigs, --list-public-keys, --list-secret-keys, and verifying  a  signature  to
              also display the photo ID attached to the key, if any. See also --photo-viewer. These options are depre-
              cated. Use --list-options [no-]show-photos and/or --verify-options [no-]show-photos instead.


       --show-keyring
              Display the keyring name at the head of key listings to show which keyring a given key resides on.  This
              option is deprecated: use --list-options [no-]show-keyring instead.



       --always-trust
              Identical to --trust-model always. This option is deprecated.


       --show-notation

       --no-show-notation
              Show  signature notations in the --list-sigs or --check-sigs listings as well as when verifying a signa-
              ture with a notation in it. These options are deprecated. Use --list-options  [no-]show-notation  and/or
              --verify-options [no-]show-notation instead.


       --show-policy-url

       --no-show-policy-url
              Show  policy URLs in the --list-sigs or --check-sigs listings as well as when verifying a signature with
              a policy URL in it. These options are deprecated. Use --list-options [no-]show-policy-url and/or  --ver-
              ify-options [no-]show-policy-url instead.






EXAMPLES
       gpg -se -r Bob file
              sign and encrypt for user Bob


       gpg --clearsign file
              make a clear text signature


       gpg -sb file
              make a detached signature


       gpg -u 0x12345678 -sb file
              make a detached signature with the key 0x12345678


       gpg --list-keys user_ID
              show keys


       gpg --fingerprint user_ID
              show fingerprint


       gpg --verify pgpfile

       gpg --verify sigfile
              Verify the signature of the file but do not output the data. The second form is used for detached signa-
              tures, where sigfile is the detached signature (either ASCII armored or binary) and are the signed data;
              if  this  is  not  given, the name of the file holding the signed data is constructed by cutting off the
              extension (".asc" or ".sig") of sigfile or by asking the user for the filename.




HOW TO SPECIFY A USER ID
       There are different ways to specify a user ID to GnuPG.  Some of them are only valid for gpg  others  are  only
       good for gpgsm.  Here is the entire list of ways to specify a key:



       By key Id.
              This  format  is  deduced  from  the length of the string and its content or 0x prefix. The key Id of an
              X.509 certificate are the low 64 bits of its SHA-1 fingerprint.  The use of key Ids is just a  shortcut,
              for all automated processing the fingerprint should be used.

              When using gpg an exclamation mark (!) may be appended to force using the specified primary or secondary
              key and not to try and calculate which primary or secondary key to use.

              The last four lines of the example give the key ID in their long form as internally used by the  OpenPGP
              protocol. You can see the long key ID using the option --with-colons.

         234567C4
         0F34E556E
         01347A56A
         0xAB123456

         234AABBCC34567C4
         0F323456784E56EAB
         01AB3FED1347A5612
         0x234AABBCC34567C4




       By fingerprint.
              This  format is deduced from the length of the string and its content or the 0x prefix.  Note, that only
              the 20 byte version fingerprint is available with gpgsm (i.e. the SHA-1 hash of the certificate).

              When using gpg an exclamation mark (!) may be appended to force using the specified primary or secondary
              key and not to try and calculate which primary or secondary key to use.

              The  best way to specify a key Id is by using the fingerprint.  This avoids any ambiguities in case that
              there are duplicated key IDs.

         1234343434343434C434343434343434
         123434343434343C3434343434343734349A3434
         0E12343434343434343434EAB3484343434343434
         0xE12343434343434343434EAB3484343434343434


       (gpgsm also accepts colons between each pair of hexadecimal digits because this is the de-facto standard on how
       to present X.509 fingerprints.)


       By exact match on OpenPGP user ID.
              This is denoted by a leading equal sign. It does not make sense for X.509 certificates.

         =Heinrich Heine <heinrichhATuni-duesseldorf.de>


       By exact match on an email address.
              This is indicated by enclosing the email address in the usual way with left and right angles.

         <heinrichhATuni-duesseldorf.de>



       By word match.
              All  words  must match exactly (not case sensitive) but can appear in any order in the user ID or a sub-
              jects name.  Words are any sequences of letters, digits, the underscore and all characters  with  bit  7
              set.

         +Heinrich Heine duesseldorf


       By exact match on the subject's DN.
              This is indicated by a leading slash, directly followed by the RFC-2253 encoded DN of the subject.  Note
              that you can't use the string printed by "gpgsm --list-keys" because that one as been reordered and mod-
              ified for better readability; use --with-colons to print the raw (but standard escaped) RFC-2253 string

         /CN=Heinrich Heine,O=Poets,L=Paris,C=FR


       By exact match on the issuer's DN.
              This is indicated by a leading hash mark, directly followed by a slash and then directly followed by the
              rfc2253 encoded DN of the issuer.  This should return the Root cert of the issuer.  See note above.

         #/CN=Root Cert,O=Poets,L=Paris,C=FR



       By exact match on serial number and issuer's DN.
              This is indicated by a hash mark, followed by the hexadecimal representation of the serial number,  then
              followed by a slash and the RFC-2253 encoded DN of the issuer. See note above.

         #4F03/CN=Root Cert,O=Poets,L=Paris,C=FR


       By keygrip
              This  is indicated by an ampersand followed by the 40 hex digits of a keygrip.  gpgsm prints the keygrip
              when using the command --dump-cert.  It does not yet work for OpenPGP keys.

         &D75F22C3F86E355877348498CDC92BD21010A480



       By substring match.
              This is the default mode but applications may want to explicitly indicate this by putting  the  asterisk
              in front.  Match is not case sensitive.

         Heine
         *Heine



       Please  note  that we have reused the hash mark identifier which was used in old GnuPG versions to indicate the
       so called local-id.  It is not anymore used and there should be no conflict when used with X.509 stuff.

       Using the RFC-2253 format of DNs has the drawback that it is not possible to map  them  back  to  the  original
       encoding, however we don't have to do this because our key database stores this encoding as meta data.





FILES
       There  are  a  few  configuration  files to control certain aspects of gpg2's operation. Unless noted, they are
       expected in the current home directory (see: [option --homedir]).



       gpg.conf
              This is the standard configuration file read by gpg2 on startup.  It may contain any valid long  option;
              the  leading two dashes may not be entered and the option may not be abbreviated.  This default name may
              be changed on the command line (see: [option --options]).  You should backup this file.


       Note that on larger installations, it is useful to put predefined files into the directory  '/etc/skel/.gnupg/'
       so  that  newly  created  users  start  up with a working configuration.  For existing users the a small helper
       script is provided to create these files (see: [addgnupghome]).

       For internal purposes gpg2 creates and maintains a few other files; They all live in in the current home direc-
       tory (see: [option --homedir]).  Only the gpg2 may modify these files.



       ~/.gnupg/secring.gpg
              The secret keyring.  You should backup this file.


       ~/.gnupg/secring.gpg.lock
              The lock file for the secret keyring.


       ~/.gnupg/pubring.gpg
              The public keyring.  You should backup this file.


       ~/.gnupg/pubring.gpg.lock
              The lock file for the public keyring.


       ~/.gnupg/trustdb.gpg
              The  trust database.  There is no need to backup this file; it is better to backup the ownertrust values
              (see: [option --export-ownertrust]).


       ~/.gnupg/trustdb.gpg.lock
              The lock file for the trust database.


       ~/.gnupg/random_seed
              A file used to preserve the state of the internal random pool.


       /usr[/local]/share/gnupg/options.skel
              The skeleton options file.


       /usr[/local]/lib/gnupg/
              Default location for extensions.


       Operation is further controlled by a few environment variables:



       HOME   Used to locate the default home directory.


       GNUPGHOME
              If set directory used instead of "~/.gnupg".


       GPG_AGENT_INFO
              Used to locate the gpg-agent.  The value consists of 3 colon delimited fields: The first is the path  to
              the Unix Domain Socket, the second the PID of the gpg-agent and the protocol version which should be set
              to 1. When starting the gpg-agent as described in its documentation, this variable is set to the correct
              value. The option --gpg-agent-info can be used to override it.


       PINENTRY_USER_DATA
              This  value  is  passed via gpg-agent to pinentry.  It is useful to convey extra information to a custom
              pinentry.


       COLUMNS

       LINES  Used to size some displays to the full size of the screen.



       LANGUAGE
              Apart from its use by GNU, it is used in the W32 version to override the language selection done through
              the Registry.  If used and set to a valid and available language name (langid), the file with the trans-
              lation is loaded from gpgdir/gnupg.nls/langid.mo.  Here gpgdir is the directory out  of  which  the  gpg
              binary  has been loaded.  If it can't be loaded the Registry is tried and as last resort the native Win-
              dows locale system is used.





BUGS
       On many systems this program should be installed as setuid(root). This is necessary to lock memory pages. Lock-
       ing  memory  pages  prevents  the  operating system from writing memory pages (which may contain passphrases or
       other sensitive material) to disk. If you get no warning message about insecure memory  your  operating  system
       supports locking without being root. The program drops root privileges as soon as locked memory is allocated.

       Note  also that some systems (especially laptops) have the ability to ''suspend to disk'' (also known as ''safe
       sleep'' or ''hibernate'').  This writes all memory to disk before going into a low power or  even  powered  off
       mode.  Unless measures are taken in the operating system to protect the saved memory, passphrases or other sen-
       sitive material may be recoverable from it later.


SEE ALSO
       gpgv(1), gpgsm(1), gpg-agent(1)

       The full documentation for this tool is maintained as a Texinfo manual.  If GnuPG  and  the  info  program  are
       properly installed at your site, the command

         info gnupg

       should give you access to the complete manual including a menu structure and an index.



GnuPG 2.0.14                      2014-06-30                           GPG2(1)