What about using the 'tty' command? It should be available in Linux: 
me@host> tty
/dev/pts/53


my $tty = `/bin/tty`;

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I *thought* that was standard for all *nix systems, but at the least it works on Solaris and several Linux distros.

In reply to Re^2: tty for each perl threads by sierpinski
in thread tty for each perl threads by ajeet@perl

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