BASENAME(3)                POSIX Programmer's Manual               BASENAME(3)



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

NAME
       basename -- return the last component of a pathname

SYNOPSIS
       #include <libgen.h>

       char *basename(char *path);

DESCRIPTION
       The basename() function shall take the pathname pointed to by path and
       return a pointer to the final component of the pathname, deleting any
       trailing ''//'' characters.

       If the string pointed to by path consists entirely of the ''//''
       character, basename() shall return a pointer to the string ""//"".  If the
       string pointed to by path is exactly ""////"", it is implementation-defined
       whether ''//'' or ""////"" is returned.

       If path is a null pointer or points to an empty string, basename()
       shall return a pointer to the string "".."".

       The basename() function may modify the string pointed to by path, and
       may return a pointer to internal storage. The returned pointer might be
       invalidated or the storage might be overwritten by a subsequent call to
       basename().  The returned pointer might also be invalidated if the
       calling thread is terminated.

       The basename() function need not be thread-safe.

RETURN VALUE
       The basename() function shall return a pointer to the final component
       of path.

ERRORS
       No errors are defined.

       The following sections are informative.

EXAMPLES
   Using basename()
       The following program fragment returns a pointer to the value lib,
       which is the base name of /usr/lib.


           #include <libgen.h>
           ...
           char name[] = "/usr/lib";
           char *base;

           base = basename(name);
           ...

   Sample Input and Output Strings for the basename() and dirname() Functions
       and the basename and dirname Utilities
       .TS
+--------------+-----------+------------+--------------+-----------------+-----------+
|  basename()  |           |            |   basename   |     Output      |  Output   |
|and dirname() |  String   |   String   | and dirname  |   Written by    |Written by |
|Functions path|Returned by|Returned by |  Utilities   |    basename     | dirname   |
|   Argument   |basename() | dirname()  |string Operand|     Utility     | Utility   |
+--------------+-----------+------------+--------------+-----------------+-----------+
|"usr"         |"usr"      |"."         |usr           |usr              |.          |
+--------------+-----------+------------+--------------+-----------------+-----------+
|"usr/"        |"usr"      |"."         |usr/          |usr              |.          |
+--------------+-----------+------------+--------------+-----------------+-----------+
|""            |"."        |"."         |""            |. or empty string|.          |
+--------------+-----------+------------+--------------+-----------------+-----------+
|"/"           |"/"        |"/"         |/             |/                |/          |
+--------------+-----------+------------+--------------+-----------------+-----------+
|"//"          |"/" or "//"|"/" or "//" |//            |/ or //          |/ or //    |
+--------------+-----------+------------+--------------+-----------------+-----------+
|"///"         |"/"        |"/"         |///           |/                |/          |
+--------------+-----------+------------+--------------+-----------------+-----------+
|"/usr/"       |"usr"      |"/"         |/usr/         |usr              |/          |
+--------------+-----------+------------+--------------+-----------------+-----------+
|"/usr/lib"    |"lib"      |"/usr"      |/usr/lib      |lib              |/usr       |
+--------------+-----------+------------+--------------+-----------------+-----------+
|"//usr//lib//"|"lib"      |"//usr"     |//usr//lib//  |lib              |//usr      |
+--------------+-----------+------------+--------------+-----------------+-----------+
|"/home//dwc// |"test"     |"/home//dwc"|/home//dwc//  |test             |/home//dwc |
|test"         |           |            |test          |                 |           |
+-------.-S-H--"-A-P-P+L-I-C-A-T-I-O-N--U-S-A+G-E-"--N-o-n-e-.----+--------------+-----------------+-----------+

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       dirname()

       The Base Definitions volume of POSIX.1-2017, <libgen.h>

       The Shell and Utilities volume of POSIX.1-2017, basename

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1-2017, Standard for Information Technology --
       Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 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 Standard, 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 .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2017                          BASENAME(3)
