Find the parent directory part of a file pathname
#include <libgen.h> char *dirname( char *path );
Use the -l c option to qcc to link against this library. This library is usually included automatically.
The dirname() function takes a pointer to a character string that contains a pathname, and returns a pointer to a string that's a pathname of the parent directory of that file. Trailing “/” characters in the path aren't counted as part of the path.
If the path doesn't contain a “/” character, or path is a NULL pointer or points to an empty string, then dirname() function returns a pointer to the string "." (dot).
Together the dirname() and basename() functions yield a complete pathname. The expression dirname(path) obtains the pathname of the directory where basename(path) is found.
|The dirname() function might modify the string pointed to by path, and can return a pointer to static storage.|
A pointer to a string that's the parent directory of path. If path is a NULL pointer or points to an empty string, a pointer to a string "." is returned.
|String input||String output|
The following code fragment reads a pathname, changes the current working directory to the parent directory, and opens the file:
char path[BUFF_SIZE], *pathcopy; int fd; fgets(path, BUFF_SIZE, stdin); pathcopy = strdup(path); chdir(dirname(pathcopy)); fd = open(basename(path), O_RDONLY);
POSIX 1003.1 XSI