I don't understand what you mean. Sure it is possible to modify a list! Just like in C, I can pass a reference to a list to be modified and it will be modified! In the code below, I am modifying the actual list since the sub uses the reference to that list. 
#!usr/bin/perl -w
use warnings;

sub modify_list
{
   my $listRef = shift;
   @$listRef = grep{!/^b/}@$listRef;
   #note there is no "return" value here
   #the list has been modified!!!!
}

my @list = ("a1", "b23", "c45", "d1", "b43", "b65");
print join (" ",@list),"\n"; 
#prints: a1 b23 c45 d1 b43 b65

modify_list(\@list);
print join (" ",@list),"\n"; 
#prints a1 c45 d1

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In reply to Re^9: Perl vs C by Marshall
in thread Perl vs C by santhosh_89

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