The essence of your complaint is correct. eval { } does not know anything about fork. After you fork, both processes continue.

Basically this comes down to people not being thorough enough when they're spawning external programs, and/or not passing through error return values from child processes as exceptions correctly.

The following constructs should be safe, and libraries using them should raise errors trappable with eval { }:

  system("foo") == 0 or die "foo failed; rc=$?";

  defined(my $pid = open FOO, "command|")
      or die "exec failed; $!";
  # ... do something with FOO ...
  close FOO;
  ($? == 0) or die "sub-process `command' failed; rc=$?";
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In general, detecting all nature of errors is outside of the scope of eval { }. As far as Perl is concerned, MIME::Lite successfully returned without noticing its sub-process failed, so there was no trappable error.

$h=$ENV{HOME};my@q=split/\n\n/,`cat $h/.quotes`;$s="$h/."
."signature";$t=`cat $s`;print$t,"\n",$q[rand($#q)],"\n";
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