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dirname(3c) [sunos man page]

dirname(3C)						   Standard C Library Functions 					       dirname(3C)

NAME
dirname - report the parent directory name of a file path name SYNOPSIS
#include <libgen.h> char *dirname(char *path); DESCRIPTION
The dirname() function takes a pointer to a character string that contains a pathname, and returns a pointer to a string that is a pathname of the parent directory of that file. Trailing '/' characters in the path are not counted as part of the path. If path does not contain a '/', then dirname() returns a pointer to the string "." . If path is a null pointer or points to an empty string, dirname() returns a pointer to the string "." . RETURN VALUES
The dirname() function returns a pointer to a string that is the parent directory of path. If path is a null pointer or points to an empty string, a pointer to a string "." is returned. ERRORS
No errors are defined. EXAMPLES
Example 1: Changing the Current Directory to the Parent Directory. The following code fragment reads a pathname, changes the current working directory to the parent directory of the named file (see chdir(2)), and opens the file. char path[[MAXPATHLEN], *pathcopy; int fd; fgets(path, MAXPATHLEN, stdin); pathcopy = strdup(path); chdir(dirname(pathcopy)); fd = open(basename(path), O_RDONLY); Example 2: Sample Input and Output Strings for dirname(). In the following table, the input string is the value pointed to by path, and the output string is the return value of the dirname() func- tion. +-----------------------------+-----------------------------+ | Input String | Output String | +-----------------------------+-----------------------------+ |"/usr/lib"" |"/usr" | +-----------------------------+-----------------------------+ |"/usr/" |"/" | +-----------------------------+-----------------------------+ |"usr" |"/" | +-----------------------------+-----------------------------+ |"/" |"/" | +-----------------------------+-----------------------------+ |"." |"." | +-----------------------------+-----------------------------+ |".." |"." | +-----------------------------+-----------------------------+ USAGE
The dirname() function modifies the string pointed to by path. The dirname() and basename(3C) functions together yield a complete pathname. The expression dirname(path) obtains the pathname of the directory where basename(path) is found. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ SEE ALSO
basename(1), chdir(2), basename(3C), attributes(5), standards(5) SunOS 5.10 18 Mar 2002 dirname(3C)

Check Out this Related Man Page

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

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 '/'. Trail- ing '/' 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).) CONFORMING TO
POSIX.1-2001. NOTES
There are two different versions of basename() - the POSIX version described above, and the GNU version, which one gets after #define _GNU_SOURCE #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 of the POSIX versions of these functions they modify their argument, and segfault when called with a static string like "/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. EXAMPLE
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 ", dname, bname); SEE ALSO
basename(1), dirname(1), feature_test_macros(7) COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/. GNU
2009-03-30 BASENAME(3)

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