This is discussed in warnings and perllexwarn; from the former:

The "warnings" pragma is a replacement for the command line flag "-w", but the pragma is limited to the enclosing block, while the flag is global.

the lowliest monk

In reply to Re: #!/usr/bin/perl -w and use warnings; by tlm
in thread #!/usr/bin/perl -w and use warnings; by ghenry

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