Visit Our UNIX and Linux User Community

Linux and UNIX Man Pages

Test Your Knowledge in Computers #483
Difficulty: Easy
IDEs do not provide automated compile/build features and other tools that make the software development process easier and faster.
True or False?
Linux & Unix Commands - Search Man Pages

dirname(3c) [opensolaris 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 5.11 18 Mar 2002 dirname(3C)

Check Out this Related Man Page

DIRNAME(3P)						     POSIX Programmer's Manual						       DIRNAME(3P)

PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the correspond- ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. NAME
dirname - report the parent directory name of a file pathname SYNOPSIS
#include <libgen.h> char *dirname(char *path); DESCRIPTION
The dirname() function shall take a pointer to a character string that contains a pathname, and return 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() shall return a pointer to the string "." . If path is a null pointer or points to an empty string, dirname() shall return a pointer to the string "." . The dirname() function need not be reentrant. A function that is not required to be reentrant is not required to be thread-safe. RETURN VALUE
The dirname() function shall return 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. The dirname() function may modify the string pointed to by path, and may return a pointer to static storage that may then be overwritten by subsequent calls to dirname(). ERRORS
No errors are defined. The following sections are informative. EXAMPLES
The following code fragment reads a pathname, changes the current working directory to the parent directory, and opens the file. char path[PATH_MAX], *pathcopy; int fd; fgets(path, PATH_MAX, stdin); pathcopy = strdup(path); chdir(dirname(pathcopy)); fd = open(basename(path), O_RDONLY); 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" "." "/" "/" "." "." ".." "." Changing the Current Directory to the Parent Directory The following program fragment reads a pathname, changes the current working directory to the parent directory, and opens the file. #include <unistd.h> #include <limits.h> #include <stdio.h> #include <fcntl.h> #include <string.h> #include <libgen.h> ... char path[PATH_MAX], *pathcopy; int fd; ... fgets(path, PATH_MAX, stdin); pathcopy = strdup(path); chdir(dirname(pathcopy)); fd = open(basename(path), O_RDONLY); APPLICATION USAGE
The dirname() and basename() functions together yield a complete pathname. The expression dirname(path) obtains the pathname of the direc- tory where basename(path) is found. Since the meaning of the leading "//" is implementation-defined, dirname(" //foo) may return either "//" or '/' (but nothing else). RATIONALE
None. FUTURE DIRECTIONS
None. SEE ALSO
basename(), the Base Definitions volume of IEEE Std 1003.1-2001, <libgen.h> COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol- ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 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 . IEEE
/The Open Group 2003 DIRNAME(3P)

Featured Tech Videos