While populating an array, (data used later for comparison), I have noticed some entries contain characters that break a regexp, a plus sign "+" for example.

I am questioning the best way to escape these characters. It seems easiest to continue pushing everything "as-is" into the array and do the escaping as needed when parsing through, but I am not sure.

Now for the obligatory coding example...
#! /usr/bin/perl -w
use strict;
my @current     = `rpm -qa`;
my @base        = `cat /tmp/install.log`;
my $cur_cnt     = @current;
my $base_cnt    = @base;

$cur_cnt        -= 1;
$base_cnt       -= 1;

foreach (@current) {
  # Reset to stay out of the negative when decrementing below.
  $base_cnt     = @base;
  # Set these because the first iteration through the
  # loop gripes about unitialized value.
  $cur_cnt      -= 1;
  $base_cnt     -= 1;
foreach (@base) {
    if ($base[$base_cnt] =~ $current[$cur_cnt]) {
      print "Unchanged: $base[$base_cnt]";
    } else {
      #Do Nothing
    }
    $base_cnt -= 1;
  }
}

[download]
This iterates through (while begging for optimization) a listing of installed RPMs, and matches against a listing of RPMs installed at build time, Any deviation, either version update or new software package is printed to the screen.

The trouble arises when the loop hits a package name with special chars, for example: timidity++-2.11.

In reply to Escaping characters in the array by penguinfuz

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