Question

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’.

Answer 1

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.

getcwd pwd