Within a module (say a.pm) used from a program (say b.pl), __FILE__ will be a.pm but $0 will be b.pl.

The test you posted checks whether the file that contains it is being run as a 'main' program, or is being used or required, or done or eval'd.

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In reply to Re: Difference between $0 and __FILE__ by BrowserUk
in thread Difference between $0 and __FILE__ by solegaonkar

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