Hi folks, thanks for your replies. I get the same results for both machines: 
me@BothMachines: perl -e'use warnings; print undef; print "done\n";'
Use of uninitialized value in print at -e line 1.
done

me@BothMachines: cat test.pl
#!/usr/bin/perl
use strict;
use warnings;
print undef;
print "done\n";

me@BothMachines: ./test.pl 
Use of uninitialized value in print at ./test.pl line 4.
done

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After playing around a bit more I realised that the location in the code where this is happening is in another perl file which I include by require. The included file does not have use statements. Are the use strict; and use warning; only applied to the current file, and not those included by require?

However, this still does not explain why it shows the warnings on one machine and not the other. I can't post work-code here, but I will construct an simple example that is equivalent and post here.

In reply to Re^2: Warnings not working on one machine by questions
in thread Warnings not working on one machine by questions

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