if( @ARGV ){
    $SIG{INT} = \&exit_gracefully;
    for(1..10){
        warn "called sleeping $_";
        select undef, undef, undef, 0.5;
    }
    exit 1;
} else {
    warn "calling system\n";
    system ( $^X, __FILE__ , 'called');

    $exit_val = $? >> 8;

    warn "\n exit_val $exit_val";
}

sub exit_gracefully
{
    $SIG{INT} = \&exit_gracefully;
    print "@ARGV Program interrupted .. \n";
    exit (2);
}
__END__
[download]

C:\>perl \dev\loose\perlfunc.exit.pl
calling system
called sleeping 1 at \dev\loose\perlfunc.exit.pl line 4.
called sleeping 2 at \dev\loose\perlfunc.exit.pl line 4.
called sleeping 3 at \dev\loose\perlfunc.exit.pl line 4.
called sleeping 4 at \dev\loose\perlfunc.exit.pl line 4.
called sleeping 5 at \dev\loose\perlfunc.exit.pl line 4.
Terminating on signal SIGINT(2)

C:\>called Program interrupted ..

C:\>
[download]

user@host:~$ perl perlfunc.exit.pl
calling system
called sleeping 1 at perlfunc.exit.pl line 4.
called sleeping 2 at perlfunc.exit.pl line 4.
called sleeping 3 at perlfunc.exit.pl line 4.
called sleeping 4 at perlfunc.exit.pl line 4.
called Program interrupted ..

 exit_val 2 at perlfunc.exit.pl line 14.
user@host:~$
user@host:~$
[download]

I tried your program and it works fine (I use Solaris), I guess the problem lies in the fact that my perl script is called from another perl script.

So if we add the following test code:
#######
# calling.pl

eval { system ("test.pl"); };
$exit_val = $? >> 8;

to call your previous test code. If I then run calling.pl and use ctrl-c, I get returned value as 0.

Mags

Here is the full code I used (I have tried also the fork-exec method) but no luck:

### Calling.pl
#!/usr/local/bin/perl -w

#eval { system ("./called.pl"); };
#$exit_value = $?;

#$exit_value = system ("./called.pl");

if ($pid2 = fork) {
# parent catches INT
print "IN PAR\n";
local $SIG{INT} = sub { print "In parent ...wait\n" };
waitpid ($pid2, 0);
}
else {
die "cannot fork: $!" unless defined $pid2;
eval { exec ("./called.pl"); };
}

print "\nE-at = $@\n";
print "\nE-! = $!\n";

print "\nE = $exit_value\n";

$exit_value = $exit_value >> 8; # Get the higher byte which has the real exit value
print "\nE1 = $exit_value\n";


### called.pl
#!/usr/local/bin/perl -w

if (@ARGV) {
$SIG{INT} = \&exit_gracefully;
for(1..10){
warn "called sleeping $_";
select undef, undef, undef, 0.5;
}
exit 1;
} else {
warn "calling system\n";
system ( $^X, __FILE__ , 'called');

$exit_val = $? >> 8;

warn "\n exit_val $exit_val";
}

sub exit_gracefully
{
$SIG{INT} = \&exit_gracefully;
print "@ARGV Program interrupted .. \n";
exit (3);
}

###Output.txt

IN PAR
calling system
called sleeping 1 at ./called.pl line 6.
called sleeping 2 at ./called.pl line 6.
called sleeping 3 at ./called.pl line 6.
called sleeping 4 at ./called.pl line 6.
^Ccalled Program interrupted ..
In parent ...wait

exit_val 3 at ./called.pl line 16.

E-at =

E-! = Interrupted system call
Use of uninitialized value in concatenation (.) or string at ./calling.pl line 22.

E =

Use of uninitialized value in right bitshift (>>) at ./calling.pl line 24.

E1 = 0

I suspect the exit value is unsigned, so your negative return code is causing a problem here. perldoc -f exit suggests that:

The only universally recognized values for EXPR are 0 for success and 1 for error; other values are subject to interpretation depending on the environment in which the Perl program is running.

Try it with some positive values and see what you get.

Well I tried exit value of 3, but still getting $? returned as 256 and when I shift it right by 8 bits I still get 1 !!!

Mags

That is odd. I used your code as the basis of a test program and got results as expected, after the system() returns, $? = 768, shift it right 8 bits and you get 3 (which is what I had called.pl exit with).

This is on Unix (HP-UX) by the way. Things may vary on other platforms - I think that is what the perldoc extract I quoted before is trying to say. What OS are you using?

---

s^^unp(;75N=&9I<V@`ack(u,^;s|\(.+\`|"$`$'\"$&\"\)"|ee;/m.+h/&&print$&