I have taken what cdarke has advised on board and tried to break it down into 6 small chunks:

# 1 - Prompt the user to enter the filename .

#2 - Verify the file extension to make sure it's htm or html.

#3 - Open the file and read each line of the file.

#4 - Change all tags to uppercase.

#5 - Tag attributes need to remain in lowercase.

#6 - Original file needs renaming with the .old extension and the processed file needs the original filename.

This is what I've got so far (not a great deal of progress).

#1

Print ("Please enter the name of your html file\n");
$file = (<STDIN>);

[download]

#2

(I have the following regular expression) ($file =~ s/html|htm$/i).

Would I be best putting this in an IF statement ?.

#3 & #4

open (IN, $file);
open (OUT, >$file);
while ($line = [IN]) {
$line =~ s/[html]/[HTML]/;<code>
# Would I have to do the above line for all possible tags or is there 
+an easier way ?.
<code>(print OUT $line);
}

[download]
Struggling on part #5 !.

#6

Got the feeling I'm going to need to use something like the following. 

rename $file, "$file.old";
open (IN, "<$file.old");
Open (OUT, ">$file");

[download]

In reply to Re^2: Converting HTML tags to upper case by Bern
in thread Converting HTML tags to upper case by Bern

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