I think we've answered this in the chatterbox. My suggestion was 

my @s = lstat $dirname or die "stat $!"; 
-l _ and die "islink $!"; 
chmod+($s[2] | 02000), $dirname or die "chmod";

[download]

If you prefer symbolic constants, you can use Fcntl "S_ISGID"; and then write S_ISGID() instead of 02000.

You could also try the File::chmod module to use symbolic mode letters.

In reply to Re: chmod in perl script by ambrus
in thread chmod in perl script by mcleary

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