Description
bool 
xdiff_file_diff ( string file1, string file2, string dest [, int context [, bool minimal]] )
     xdiff_file_diff() makes unified diff of files
     file1 and file2 and stores
     result in file dest.
     context indicated how many lines of context you
     want to include in diff result. Set minimal to
     TRUE if you want to minimalize size of diff (can take a long time).
     Resulting file is human-readable.
    
     Returns TRUE on success or FALSE on failure.
    
| Example 1. xdiff_file_diff() example 
      The following code makes unified diff of two php files.
      | <?php
$old_version = 'my_script.php';
$new_version = 'my_new_script.php';
xdiff_file_diff($old_version, $new_version, 'my_script.diff', 2);
?> | 
 | 
     See also xdiff_string_diff().