How to get the directory path and file name from a absolute path in C on Linux

How to get the directory path and file name from a absolute path in C on Linux?

For example, with "/foo/bar/baz.txt", it will produce: "/foo/bar/" and "baz.txt".

You can use the APIs basename and dirname to parse the file name and directory name.

A piece of C code:

#include <libgen.h>
#include <string.h>

char* local_file = "/foo/bar/baz.txt";

char* ts1 = strdup(local_file);
char* ts2 = strdup(local_file);

char* dir = dirname(ts1);
char* filename = basename(ts2);

// use dir and filename now
// dir: "/foo/bar"
// filename: "baz.txt"

Note:

  1. dirname and basename return pointers to null-terminated strings. Do not try to free them.
  2. There are two different versions of basename—the POSIX version and the GNU version.
  3. The POSIX version of dirname and basename may modify the content of the argument. Hence, we need to strdup the local_file.
  4. The GNU version of basename never modifies its argument.
  5. There is no GNU version of dirname().
Answered by Eric Z Ma.

Eric Z Ma

Eric is a father and systems guy. Eric is interested in building high-performance and scalable distributed systems and related technologies. The views or opinions expressed here are solely Eric's own and do not necessarily represent those of any third parties.

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