NAME

       basename, dirname - parse pathname components

SYNOPSIS

       #include <libgen.h>

       char *dirname(char *path);

       char *basename(char *path);

DESCRIPTION

       Warning: there are two different functions basename() - see below.

       The  functions  dirname()  and  basename()  break  a  null-terminated  pathname string into directory and
       filename components.  In the usual case, dirname() returns the string up to, but not including, the final
       '/',  and  basename()  returns  the  component  following the final '/'.  Trailing '/' characters are not
       counted as part of the pathname.

       If path does not contain a slash, dirname() returns the string "." while basename()  returns  a  copy  of
       path.  If path is the string "/", then both dirname() and basename() return the string "/".  If path is a
       null pointer or points to an empty string, then both dirname() and basename() return the string ".".

       Concatenating the string returned by dirname(), a "/", and the string returned  by  basename()  yields  a
       complete pathname.

       Both dirname() and basename() may modify the contents of path, so it may be desirable to pass a copy when
       calling one of these functions.

       These functions may return pointers to statically allocated memory which may be overwritten by subsequent
       calls.   Alternatively, they may return a pointer to some part of path, so that the string referred to by
       path should not be modified or freed until the pointer returned by the function is no longer required.

       The following list of examples (taken from SUSv2) shows the strings returned by dirname() and  basename()
       for different paths:

              path       dirname   basename
              /usr/lib   /usr      lib
              /usr/      /         usr
              usr        .         usr
              /          /         /
              .          .         .
              ..         .         ..

RETURN VALUE

       Both dirname() and basename() return pointers to null-terminated strings.  (Do not pass these pointers to
       free(3).)

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌──────────────────────┬───────────────┬─────────┐
       │Interface             │ Attribute     │ Value   │
       ├──────────────────────┼───────────────┼─────────┤
       │basename(), dirname() │ Thread safety │ MT-Safe │
       └──────────────────────┴───────────────┴─────────┘

CONFORMING TO

       POSIX.1-2001, POSIX.1-2008.

NOTES

       There are two different versions of basename() - the POSIX version described above, and the GNU  version,
       which one gets after

               #define _GNU_SOURCE         /* See feature_test_macros(7) */
               #include <string.h>

       The GNU version never modifies its argument, and returns the empty string when path has a trailing slash,
       and in particular also when it is "/".  There is no GNU version of dirname().

       With glibc, one gets the POSIX version of basename() when <libgen.h> is included,  and  the  GNU  version
       otherwise.

BUGS

       In the glibc implementation, the POSIX versions of these functions modify the path argument, and segfault
       when called with a static string such as "/usr/".

       Before glibc 2.2.1, the glibc version of dirname() did not correctly handle pathnames with  trailing  '/'
       characters, and generated a segfault if given a NULL argument.

EXAMPLES

       The following code snippet demonstrates the use of basename() and dirname():
           char *dirc, *basec, *bname, *dname;
           char *path = "/etc/passwd";

           dirc = strdup(path);
           basec = strdup(path);
           dname = dirname(dirc);
           bname = basename(basec);
           printf("dirname=%s, basename=%s\n", dname, bname);

SEE ALSO

       basename(1), dirname(1)

COLOPHON

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