Here's a complete program, demonstrating the correct solution given above: 
#!/usr/bin/perl -w

use strict;

my $path = "/foo/mik/../mik/./../mik";
# print "Path is --$path--\n";
    $path =~ s!/\.([^.])!$1!g;
# print "Path is now --$path--\n";
while ($path =~ m!/\.!) {
    $path =~ s!/[^\/]+/\.\.!!;
# print "Path is now -+$path+-\n";
}

print "Ended up with =>>$path<<=\n";

[download]
First, we get rid of /., because that won't take us anywhere. Next we loop while there's a dot followed by a forward slash. As /.. takes us up a directory, we look for a valid directory followed by that construct, and get rid of the whole thing. Eventually, the loop has to fail, and we must have come up with something.

merlyn and turnstep are correct, though -- doing this sort of thing with regular expressions is pretty easy to break. Unless you have *complete* control of the directories being passed to your script and in the filesystem, don't use this.

In reply to Re: Normalized directory paths by chromatic
in thread Normalized directory paths by mikfire

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