Man Pages

basename(1p) - phpMan basename(1p) - phpMan

Command: man perldoc info search(apropos)  


BASENAME(1P)               POSIX Programmer's Manual              BASENAME(1P)



PROLOG
       This manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may dif-
       fer (consult the corresponding Linux manual page for details of Linux behavior), or the interface  may  not  be
       implemented on Linux.

NAME
       basename - return non-directory portion of a pathname

SYNOPSIS
       basename string [suffix]

DESCRIPTION
       The  string  operand  shall  be  treated  as  a  pathname,  as  defined  in  the  Base  Definitions  volume  of
       IEEE Std 1003.1-2001, Section 3.266, Pathname. The string string shall be converted to the filename correspond-
       ing  to  the last pathname component in string and then the suffix string suffix, if present, shall be removed.
       This shall be done by performing actions equivalent to the following steps in order:

        1. If string is a null string, it is unspecified whether the resulting string is '.'  or  a  null  string.  In
           either case, skip steps 2 through 6.


        2. If string is "//", it is implementation-defined whether steps 3 to 6 are skipped or processed.


        3. If  string  consists entirely of slash characters, string shall be set to a single slash character. In this
           case, skip steps 4 to 6.


        4. If there are any trailing slash characters in string, they shall be removed.


        5. If there are any slash characters remaining in string, the prefix of string up to and  including  the  last
           slash character in string shall be removed.


        6. If  the suffix operand is present, is not identical to the characters remaining in string, and is identical
           to a suffix of the characters remaining in string, the suffix suffix shall be removed from  string.  Other-
           wise,  string  is  not modified by this step. It shall not be considered an error if suffix is not found in
           string.


       The resulting string shall be written to standard output.

OPTIONS
       None.

OPERANDS
       The following operands shall be supported:

       string A string.

       suffix A string.


STDIN
       Not used.

INPUT FILES
       None.

ENVIRONMENT VARIABLES
       The following environment variables shall affect the execution of basename:

       LANG   Provide a default value for the internationalization variables that are unset or  null.  (See  the  Base
              Definitions  volume  of IEEE Std 1003.1-2001, Section 8.2, Internationalization Variables for the prece-
              dence of internationalization variables used to determine the values of locale categories.)

       LC_ALL If set to a non-empty string value, override the values of all the other internationalization variables.

       LC_CTYPE
              Determine  the locale for the interpretation of sequences of bytes of text data as characters (for exam-
              ple, single-byte as opposed to multi-byte characters in arguments).

       LC_MESSAGES
              Determine the locale that should be used to affect the format and contents of diagnostic messages  writ-
              ten to standard error.

       NLSPATH
              Determine the location of message catalogs for the processing of LC_MESSAGES .


ASYNCHRONOUS EVENTS
       Default.

STDOUT
       The basename utility shall write a line to the standard output in the following format:


              "%s\n", <resulting string>

STDERR
       The standard error shall be used only for diagnostic messages.

OUTPUT FILES
       None.

EXTENDED DESCRIPTION
       None.

EXIT STATUS
       The following exit values shall be returned:

        0     Successful completion.

       >0     An error occurred.


CONSEQUENCES OF ERRORS
       Default.

       The following sections are informative.

APPLICATION USAGE
       The  definition  of  pathname  specifies  implementation-defined behavior for pathnames starting with two slash
       characters.  Therefore, applications shall not arbitrarily add slashes to the beginning of  a  pathname  unless
       they  can  ensure  that there are more or less than two or are prepared to deal with the implementation-defined
       consequences.

EXAMPLES
       If the string string is a valid pathname:


              $(basename "string")

       produces a filename that could be used to open the file named by string in the directory returned by:


              $(dirname "string")

       If the string string is not a valid pathname, the same algorithm is used, but the result need not  be  a  valid
       filename.   The basename utility is not expected to make any judgements about the validity of string as a path-
       name; it just follows the specified algorithm to produce a result string.

       The following shell script compiles /usr/src/cmd/cat.c and moves the output to a file named cat in the  current
       directory when invoked with the argument /usr/src/cmd/cat or with the argument /usr/src/cmd/cat.c:


              c99 $(dirname "$1")/$(basename "$1" .c).c
              mv a.out $(basename "$1" .c)

RATIONALE
       The behaviors of basename and dirname have been coordinated so that when string is a valid pathname:


              $(basename "string")

       would be a valid filename for the file in the directory:


              $(dirname "string")

       This  would not work for the early proposal versions of these utilities due to the way it specified handling of
       trailing slashes.

       Since the definition of pathname specifies implementation-defined behavior  for  pathnames  starting  with  two
       slash characters, this volume of IEEE Std 1003.1-2001 specifies similar implementation-defined behavior for the
       basename and dirname utilities.

FUTURE DIRECTIONS
       None.

SEE ALSO
       Parameters and Variables, dirname()

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Stan-
       dard  for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifica-
       tions Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers,  Inc  and  The
       Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Stan-
       dard, the original IEEE and The Open Group Standard is the referee  document.  The  original  Standard  can  be
       obtained online at http://www.opengroup.org/unix/online.html .



IEEE/The Open Group                  2003                         BASENAME(1P)