Your program works as you expected (if you close the double quotes) but you can't see the output because STDOUT is buffered. If you change the alarm proc as follows

$SIG{ALRM} = sub {print "checking;\n"};

it works.

Rule One: "Do not act incautiously when confronting a little bald wrinkly smiling man."

In reply to Re: How to use alarm? by psini
in thread How to use alarm? by stephenp

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