Reports the parent directory name of a file pathname.

    Format

      #include  <libgen.h>

      char *dirname  (char *path);

1 - Function Variants

    The dirname function has variants named _dirname32 and _dirname64
    for use with 32-bit and 64-bit pointer sizes, respectively.

2 - Argument

 path

    The file pathname.

3 - Description

    The dirname function takes a pointer to a character string that
    contains a UNIX pathname and returns a pointer to a string that
    is a pathname of the parent directory of that file. Trailing
    slash (/)  characters in the path are not counted as part of the
    path.

    This function returns a pointer to the string "." (dot), when the
    path argument:

    o  Does not contain a slash (/).

    o  Is a NULL pointer.

    o  Points to an empty string.

    The dirname function can modify the string pointed to by the path
    argument.

    The dirname and basename functions together yield a complete
    pathname. The expression dirname(path) obtains the pathname of
    the directory where basename(path) is found.

    See also basename.

4 - Return Values

    x                  A pointer to a string that is the parent
                       directory of the path argument.
    "."                The path argument:

                       o  Does not contain a slash (/).

                       o  Is a NULL pointer.

                       o  Points to an empty string.

5 - Example

      Using the dirname function, the following example reads a
      pathname, changes the current working directory to the parent
      directory, and opens a file.

            char path [MAXPATHLEN], *pathcopy;
            int fd;

            fgets(path, MAXPATHLEN, stdin);
            pathcopy = strdup(path);
            chdir(dirname(pathcopy));
            fd = open(basename(path), O_RDONLY);