Hi L~R,
thank's for the very quick and helpful response. According to perlipc I shall (probably) use: 
Instead of setting $SIG{ALRM} :
    local $SIG{ALRM} = sub { die "alarm" };

try something like the following:
    use POSIX qw(SIGALRM);
    POSIX::sigaction(SIGALRM,
        POSIX::SigAction->new(sub { die "alarm" }))
          or die "Error setting SIGALRM handler: $!\n";

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In reply to Re^2: timeout problem with alarm by Anonymous Monk
in thread timeout problem with alarm by Anonymous Monk

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