use strict;
my $temp = shift @ARGV || 0;
print "call no. $temp\n";
if ( $temp < 10 )
{
    system ("rec.pl", $temp+1);
}
[download]

call no. 0
call no. 1
call no. 2
call no. 3
call no. 4
call no. 5
call no. 6
call no. 7
call no. 8
call no. 9
call no. 10
[download]

I think you need to show us some code. My guess is that you are using some kind of global variable, which means that you will need to rewrite your code to save the old value, set the new value, recurse, and then restore the old value again. The following Perl code works fine with recursing and automatically resets the old value:

use strict;

print ackermann(3,3);

sub ackermann {
  my ($left,$right) = @_;
  print "$left,$right\n";
  if ($left == 0) {
    return $right+1
  } elsif ($right == 0) {
    return ackermann($left-1, 1)
  } else {
    return ackermann($left-1, ackermann($left, $right-1))
  };
};
[download]

The trick is, that this code does not use respectively change any global variables, and thus has no problems invoking itself.

...when script is called recursively

Independent scripts simply don't share variables.

Indeed, that sentence confused me. The OP might have meant when the function is called recursively ... Here is some code for the OP that shows how to maintain a "global" variable, but not how to share variables between runs of a script.

#!/usr/bin/perl

use strict;
use warnings;

our $outer = 5;
recurse($outer);

sub recurse {
    my $inner = shift;
    $inner--;
    return if $inner < 0;
    print "outer: $outer\ninner: $inner\n";
    recurse($inner);
}
[download]

UPDATE: You make it seem so crystal clear, holli. Oh well, here is a recursive sub in case someone needs it. :D

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

The OP said my script calls itself recursively. I think that has be to taken as it was said. There may be a good reason to do that.

holli, regexed monk

Yes, wary is the word, if the script get posted im expecting to see the dreaded exec in there ...





Im so sick of my Signature...

What you are looking for is called a static variable in other languages. The Perl FAQ talks about how to get something similar in How do I create a static variable

You can store your variable in a file. Start your program with any "invalid" value of the variable, e.g. undef. Then initialize it only if it's value is "invalid".

$temp = read_from_file();
$temp = 1 unless defined $temp;
store_to_file($temp);
[download]