Hi, i had the problem that the contents of $@ produced by a failed eval{...} looked wired. It turned out that this was caused by a module that set the $SIG{__DIE__} handler. I then tried this:
use strict;
use warnings;
# Just to demonstrate the problem:
$SIG{__DIE__} = sub {die "[Unwanted stuff] @_"};
eval {
local %SIG;
die("Something is wrong!\n");
};
print "Got: $@\n";
But i got: Got: [Unwanted stuff] Something is wrong!. Obviously, the handler is still active inside the eval{...}. Looking at perlmonks i found this http://www.perlmonks.org/?node_id=51097 and changed my code to:
use strict;
use warnings;
# Just to demonstrate the problem:
$SIG{__DIE__} = sub {die "[Unwanted stuff] @_"};
eval {
local $SIG{__DIE__}; # No sigdie handler
die("Something is wrong!\n");
};
print "Got: $@\n";
Now the output is Got: Something is wrong!, meaning that the handler is switched off, which is the desired result.
But i still do not understand why my fist approach didn't work. Why does local %SIG; not turn off the handler? I expected this to just turn off all handlers. Why do i need to write local $SIG{__DIE__};? Can anybody explain this?
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