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



PPRROOLLOOGG
       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.

NNAAMMEE
       basename -- return the last component of a pathname

SSYYNNOOPPSSIISS
       #include <libgen.h>

       char *basename(char *_p_a_t_h);

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

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

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

       The _b_a_s_e_n_a_m_e() function may modify the string pointed to by _p_a_t_h, 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
       _b_a_s_e_n_a_m_e().  The returned pointer might also be invalidated if the
       calling thread is terminated.

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

RREETTUURRNN VVAALLUUEE
       The _b_a_s_e_n_a_m_e() function shall return a pointer to the final component
       of _p_a_t_h.

EERRRROORRSS
       No errors are defined.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

EEXXAAMMPPLLEESS
   UUssiinngg bbaasseennaammee(())
       The following program fragment returns a pointer to the value _l_i_b,
       which is the base name of //uussrr//lliibb.


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

           base = basename(name);
           ...

   SSaammppllee IInnppuutt aanndd OOuuttppuutt SSttrriinnggss ffoorr tthhee bbaasseennaammee(()) aanndd ddiirrnnaammee(()) FFuunnccttiioonnss
       aanndd tthhee bbaasseennaammee aanndd ddiirrnnaammee UUttiilliittiieess
       .TS
+--------------+-----------+------------+--------------+-----------------+-----------+
|  bbaasseennaammee(())  |           |            |   bbaasseennaammee   |     OOuuttppuutt      |  OOuuttppuutt   |
|aanndd ddiirrnnaammee(()) |  SSttrriinngg   |   SSttrriinngg   | aanndd ddiirrnnaammee  |   WWrriitttteenn bbyy    |WWrriitttteenn bbyy |
|FFuunnccttiioonnss ppaatthh|RReettuurrnneedd bbyy|RReettuurrnneedd bbyy |  UUttiilliittiieess   |    bbaasseennaammee     | ddiirrnnaammee   |
|   AArrgguummeenntt   |bbaasseennaammee(()) | ddiirrnnaammee(())  |ssttrriinngg OOppeerraanndd|     UUttiilliittyy     | UUttiilliittyy   |
+--------------+-----------+------------+--------------+-----------------+-----------+
|"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-.----+--------------+-----------------+-----------+

RRAATTIIOONNAALLEE
       None.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       _d_i_r_n_a_m_e()

       The Base Definitions volume of POSIX.1-2017, <<lliibbggeenn..hh>>

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

CCOOPPYYRRIIGGHHTT
       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)
