hi all,
is it a known problem that alarm() function doesn't work as expected? The following code (see 'perl cookbook' or 'perldoc -f alarm') doesn't terminate after 5 seconds - it waits till ping timeouts (db01 is a known down host): 

my $timeout = 5;
eval {
    local $SIG{ALRM} = sub { die "alarm\n" }; # NB: \n required
    alarm $timeout;
    my $ret = qx/ping db01/;
    alarm 0;
};
if ($@) { # timed out
    print "timeout handling ($! - $@) ...\n";
    die unless $@ eq "alarm\n";   # propagate unexpected errors
}
else { # didn't
    print "no timeout timeout handling...\n";
}

[download]

I am writing watchdog scripts an I need response from the clients whithin a defined timeout period.

Any suggestions?

TIA

Retitled by g0n from 'timout problem with alarm'.

In reply to timeout problem with alarm by Anonymous Monk

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