C:\>perl -w tmp.pl Name "main::IN" used only once: possible typo at tmp.pl line 8. Use of uninitialized value $id in seek at tmp.pl line 10. seek() on unopened filehandle In at tmp.pl line 10. readline() on unopened filehandle In at tmp.pl line 11. Use of uninitialized value $name in concatenation (.) or string at tmp.pl line 3.