The Tor Browser / file revision

 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this

  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

 #include <unistd.h>

 #include <stdio.h>

 int main(int argc, char **argv)

 {

   if (argc != 2)

     return 1;

   uid_t realuser = getuid();

   char uidstring[20];

   snprintf(uidstring, 19, "%i", realuser);

   uidstring[19] = '\0';

   return execl("/usr/sbin/chown",

                "/usr/sbin/chown", "-R", "-h", uidstring, argv[1], (char*) 0);

 }