Given an absolute or relative path (in a Unix-like system), I would like to determine the full path of the target after resolving any intermediate symlinks. Bonus points for also resolving ~username notation at the same time.
If the target is a directory, it might be possible to chdir() into the directory and then call getcwd(), but I really want to do this from a shell script rather than writing a C helper. Unfortunately, shells have a tendency to try to hide the existence of symlinks from the user (this is bash on OS X):
$ ls -ld foo bar
drwxr-xr-x 2 greg greg 68 Aug 11 22:36 bar
lrwxr-xr-x 1 greg greg 3 Aug 11 22:36 foo -> bar
$ cd foo
$ pwd
/Users/greg/tmp/foo
$
What I want is a function resolve() such that when executed from the tmp directory in the above example, resolve("foo") == "/Users/greg/tmp/bar".
According to the standards, pwd -P should return the path with symlinks resolved.
C function char *getcwd(char *buf, size_t size) from unistd.h should have the same behaviour.