man Pages(3): Library Routines

dirname(3C)

NAME

dirname- report the parent directory name of a file path name

SYNOPSIS

#include <libgen.h>

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 A sample code using the `dirname()` function.

`Input String`	`Output String`
"/usr/lib""	"/usr"
"/usr/"	"/"
"usr"	"/"
"/"	"/"
"."	"."
".."	"."

The following code fragment reads a path name, changes directory to the parent directory of the named file (see chdir(2)), and opens the file.

char path[100], *pathcopy;
int fd;
gets (path);
pathcopy = strdup (path);
chdir (dirname (pathcopy) );
free (pathcopy);
fd = open (basename (path), O_RDONLY);

USAGE

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().

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.

When compiling multithreaded applications, the _REENTRANT flag must be defined on the compile line. This flag should only be used in multithreaded applications.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
MT-Level	MT-Safe