You don't have to return anything to change an array. 
#!/usr/bin/perl
sub plus {
   for (@_) {$_++}
}
my @foo=(1,2,3,4);
plus(@foo);
for(@foo) {print "$_\n"};

[download]
Prints out: 
2
3
4
5

In reply to Re: Array value changing for some reason by kschwab
in thread Array value changing for some reason by Silt

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