in reply to Testing <> for undefined

If you're asking how to see if there are command line arguments, the arguments are copied into @ARGV. Check the length of that array. If it's empty, then you have no args: 
if (@ARGV) {
  # you have command line args
} else {
  # ya don't!
}

[download]

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In Section Seekers of Perl Wisdom