Man Pages

err(3) - phpMan err(3) - phpMan

Command: man perldoc info search(apropos)  

err(3)                              OpenSSL                             err(3)

       err - error codes

        #include <openssl/err.h>

        unsigned long ERR_get_error(void);
        unsigned long ERR_peek_error(void);
        unsigned long ERR_get_error_line(const char **file, int *line);
        unsigned long ERR_peek_error_line(const char **file, int *line);
        unsigned long ERR_get_error_line_data(const char **file, int *line,
                const char **data, int *flags);
        unsigned long ERR_peek_error_line_data(const char **file, int *line,
                const char **data, int *flags);

        int ERR_GET_LIB(unsigned long e);
        int ERR_GET_FUNC(unsigned long e);
        int ERR_GET_REASON(unsigned long e);

        void ERR_clear_error(void);

        char *ERR_error_string(unsigned long e, char *buf);
        const char *ERR_lib_error_string(unsigned long e);
        const char *ERR_func_error_string(unsigned long e);
        const char *ERR_reason_error_string(unsigned long e);

        void ERR_print_errors(BIO *bp);
        void ERR_print_errors_fp(FILE *fp);

        void ERR_load_crypto_strings(void);
        void ERR_free_strings(void);

        void ERR_remove_state(unsigned long pid);

        void ERR_put_error(int lib, int func, int reason, const char *file,
                int line);
        void ERR_add_error_data(int num, ...);

        void ERR_load_strings(int lib,ERR_STRING_DATA str[]);
        unsigned long ERR_PACK(int lib, int func, int reason);
        int ERR_get_next_error_library(void);

       When a call to the OpenSSL library fails, this is usually signalled by the return value, and an error code is
       stored in an error queue associated with the current thread. The err library provides functions to obtain these
       error codes and textual error messages.

       The ERR_get_error(3) manpage describes how to access error codes.

       Error codes contain information about where the error occurred, and what went wrong. ERR_GET_LIB(3) describes
       how to extract this information. A method to obtain human-readable error messages is described in

       ERR_clear_error(3) can be used to clear the error queue.

       Note that ERR_remove_state(3) should be used to avoid memory leaks when threads are terminated.

       See ERR_put_error(3) if you want to record error codes in the OpenSSL error system from within your

       The remainder of this section is of interest only if you want to add new error codes to OpenSSL or add error
       codes from external libraries.

   Reporting errors
       Each sub-library has a specific macro XXXerr() that is used to report errors. Its first argument is a function
       code XXX_F_..., the second argument is a reason code XXX_R_.... Function codes are derived from the function
       names; reason codes consist of textual error descriptions. For example, the function ssl23_read() reports a
       "handshake failure" as follows:


       Function and reason codes should consist of upper case characters, numbers and underscores only. The error file
       generation script translates function codes into function names by looking in the header files for an
       appropriate function name, if none is found it just uses the capitalized form such as "SSL23_READ" in the above

       The trailing section of a reason code (after the "_R_") is translated into lower case and underscores changed
       to spaces.

       When you are using new function or reason codes, run make errors.  The necessary #defines will then
       automatically be added to the sub-library's header file.

       Although a library will normally report errors using its own specific XXXerr macro, another library's macro can
       be used. This is normally only done when a library wants to include ASN1 code which must use the ASN1err()

   Adding new libraries
       When adding a new sub-library to OpenSSL, assign it a library number ERR_LIB_XXX, define a macro XXXerr() (both
       in err.h), add its name to ERR_str_libraries[] (in crypto/err/err.c), and add "ERR_load_XXX_strings()" to the
       ERR_load_crypto_strings() function (in crypto/err/err_all.c). Finally, add an entry

        L      XXX     xxx.h   xxx_err.c

       to crypto/err/, and add xxx_err.c to the Makefile.  Running make errors will then generate a file
       xxx_err.c, and add all error codes used in the library to xxx.h.

       Additionally the library include file must have a certain form.  Typically it will initially look like this:

        #ifndef HEADER_XXX_H
        #define HEADER_XXX_H

        #ifdef __cplusplus
        extern "C" {

        /* Include files */

        #include <openssl/bio.h>
        #include <openssl/x509.h>

        /* Macros, structures and function prototypes */

        /* BEGIN ERROR CODES */

       The BEGIN ERROR CODES sequence is used by the error code generation script as the point to place new error
       codes, any text after this point will be overwritten when make errors is run.  The closing #endif etc will be
       automatically added by the script.

       The generated C error code file xxx_err.c will load the header files stdio.h, openssl/err.h and openssl/xxx.h
       so the header file must load any additional header files containing any definitions it uses.

       It is also possible to use OpenSSL's error code scheme in external libraries. The library needs to load its own
       codes and call the OpenSSL error code insertion script explicitly to add codes to the header file and
       generate the C error code file. This will normally be done if the external library needs to generate new ASN1
       structures but it can also be used to add more general purpose error code handling.

       TBA more details

       The error queues are stored in a hash table with one ERR_STATE entry for each pid. ERR_get_state() returns the
       current thread's ERR_STATE. An ERR_STATE can hold up to ERR_NUM_ERRORS error codes. When more error codes are
       added, the old ones are overwritten, on the assumption that the most recent errors are most important.

       Error strings are also stored in hash table. The hash tables can be obtained by calling
       ERR_get_err_state_table(void) and ERR_get_string_table(void) respectively.

       CRYPTO_set_id_callback(3), CRYPTO_set_locking_callback(3), ERR_get_error(3), ERR_GET_LIB(3),
       ERR_clear_error(3), ERR_error_string(3), ERR_print_errors(3), ERR_load_crypto_strings(3), ERR_remove_state(3),
       ERR_put_error(3), ERR_load_strings(3), SSL_get_error(3)

1.0.1e                            2013-02-11                            err(3)