You can't do this (well you can but it won't DWIM):

eval {
system("perl 2.pl");
};
if($@) {
 print "the error that was thrown in 2.pl";
}
...
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all it does is see if system("perl 2.pl") is valid perl regardless of 1) whether the system call succeeds or fails and 2) what happens when 2.pl actually runs. A system call may confuse you because if it *succeeds* it will return 0 (false) and if it fails it will return true! Thus you can't do:

system("blah") or die "Can't blah $!\n";
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because this will die when it works! The reason is that in *nix programing if a program suceeds it exits with a value of 0. If it fails it exits with a numerical value that corresponds to the error code.

In the real world, in 1.pl you would have:

my $ret_val = system("perl 2.pl");
if ( $ret_val == 0 ) {
    print "Success";
}
else {
    printf "Error. Err Number: %d", $ret_val<<8;
}
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And in 2.pl you would have:

exit 0        if $success;
exit $err_num if $err_num;  # numerical error value
exit -1;                    # WTF???
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Usually you would exit with the error number or exit 0 at the (sucessful) end of the script.

open F, $file or do {
    warn "Can't open $file for read $!\n";
    exit 1;    # Error code for can't open file
}
do_stuff(*F);
close F;
exit 0;
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