If you're interested in emitting warnings with filenames and line numbers, you might want warn(), which is documented in perlfunc. 
    warn "I'm a warning about something";

[download]
will produce 
  I'm a warning about something at demo.pl line 47.

[download]

die() does the same, but stops execution (unless caught in an exception handler).

In reply to Re: __FILE__ and __LINE__ for Perl? by dws
in thread __FILE__ and __LINE__ for Perl? by Plankton

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