To prevent from destroying the symlinks, I found the solutions, but they did not work. Should it be applied to Perl or Bash/Shell?

In the continuation of Is it bad to use the conditions for finding the directories and to cd multiple specific folders of a found directory to call the function?, I would like to preserve the symlnks, but I am not sure if it should be applied to Perl or to Bash/Shell. The guys gave me the solutions, but I tested and it did not work.

My original:

for f in *svg; do
  case "$color" in
    a)
          perl arrogrin.pl "$f" > tmpFile && mv tmpFile "$f"
          ;;
      black)
          perl black.pl "$f" > tmpFile && mv tmpFile "$f"
          ;;
    esac
    done

The file arrogin.pl:

#!/bin/perl
my $replacement=<<EoF;
<linearGradient id="grad" x1="0%" y1="0%" x2="0%" y2="100%">
  <stop offset="0%" style="stop-color: #dd9b44; stop-opacity: 1" />
  <stop offset="100%" style="stop-color: #ad6c16; stop-opacity: 1" />
</linearGradient>
EoF

## This is just to fix SE's syntax highlighting /    
my $foundSvg = 0;
while (<>) 
{

  ## Insert the replacement after the 1st line matching '<svg'
  if (/<\s*svg/) 
  {
    $foundSvg++;
  }
  if ($foundSvg == 1) 
  {

    ## $_ is the value of the current line. If we have found the <svg,
    ## append $replacement to this line
    $_ .= $replacement;

    ## Increment $foundSvg so we don't do this twice
    $foundSvg++;
  }

  ## For all lines, replace all occurrences of #5c616c with url(#grad1)
  s/#5c616c/url(#grad)/g;
  ## Print the line
  print;
}

The file black.pl:

#!/bin/perl
use strict; use warnings;

while (<>) 
{

  ## For all lines, replace all occurrences of #5c616c with another colour
  s/#5c616c/#404747/g

  ## Print the line
  print;
}

The guys gave me the solutions, both almost worked, both preserved the symlinks, but they made all them unusable. Here are:

fool.pl:

#!/usr/bin/env perl
use strict;
use warnings;

for my $arg (@ARGV) 
{
    $arg = readlink $arg if -l $arg;
}

# in-place edit with backup filename, perldoc -v '$^I'
$^I = ".whoops";

while (readline) 
{
    s/#5c616c/#8bbac9/g;
    print;
}

And I modified the original:

for f in *svg; do
  case "$color" in
    a)
          perl arrogrin.pl "$f" > tmpFile && mv tmpFile "$(readlink -f "$f")"
          ;;
      black)
          perl black.pl "$f" > tmpFile && mv tmpFile "$(readlink -f "$f")"
          ;;
    esac
    done

Observations: I would like to replace Perl files for Bash files, because Bash offers --in-place --follow-symlinks, but I am not sure I can something similar in Bash to that in Perl.