Two suggestions:
  1. Use File::Find with File::Glob. One for digging into sub directories, the other one for matching .shtml files. Much less coding on your own.
  2. When you read files, call read with a big buffer, to read in the whole shtml file by one call. This improves performance. Don't handle line by line, too slow. Memory is not an issue in your case(, unless you have huge shtml files). When you s///, use /g modifier.
  3. Don't consider +< in this case, as your new content is shorter than the old one. (I am not saying you cannot use it, but using it in this case, requires more coding effort) 
use File::Find;
use File::Glob ':glob';

use strict;

find(\&wanted, "c:/perl58/bin"); #replace with your directory

sub wanted {
    if ((-d $File::Find::name) && ($_ ne ".") && ($_ ne "..")) {
        my @shtml_files = bsd_glob("*.shtml");
        foreach my $shtml_file (@shtml_files) {
            print $shtml_file;
            open(SHTMLFILE, "<", $shtml_file);
            my $buffer;
            read(SHTMLFILE, $buffer, 10000); #give some big number, wh
+ich exceeds the size of all your .shtml files   
            close(SHTMLFILE); 
            $buffer =~ s/<a href="main\.php\?page=(.*?)\"/<a href="mai
+n.php?id=$1"/g;
            open(SHTMLFILE, ">", $shtml_file); 
            close(SHTMLFILE); 
        }
    }       
}

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In reply to Re: Massive File Editing by pg
in thread Massive File Editing by Kage

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