Thanks, I have absolute paths. Below is my entire code if it helps. 
use strict;
use warnings;
use File::Slurp qw/read_file/;
use CGI;


print CGI::header();

my $htmlfile ='/var/www/html/xx/xxx/1204.html';
#mainfile to read
my  $html =read_file($htmlfile);
#path of the included file
my $includepath="/var/www/html/xx/xxx/";


if ($html =~ s{#include file="([^"]+)"}{&add_template($1)}gei)
    {
        print "the file has include file";
        print $html;
    }
    else
    {
        print "doesn't have";
        print $html;
    }



sub add_template{
      my $file = shift;
        #print "$file";
        my $display_file="$includepath$file";
        # print $display_file;
         if (-e $display_file){
             #print "$display_file";
             return read_file($display_file);

            } else {
            # warn "$display_file not found";
            return '<!-- $display_file not found to include -->';
                         }
}

[download]
The above code prints the main file which is 1204.html and then also detects that there is an included file given in the if condition but just doesn't print it. Not sure why. Many Thanks, T

In reply to Re^8: displaying html file in the browser using perl by tsdesai
in thread displaying html file in the browser using perl by tsdesai

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