The following code is opening the file for writing(thereby erasing the contents), but really printing nothing to it

open (OUTFILE, ">E:/Documents and Settings/Richard Lamb/My Documents/H
+TML/dummy.html") or die("$!: Can't write to the HTML file.\n");
print (OUTFILE);
close (OUTFILE);
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I think this may be what you want. Printing to the outfile in the loop

open (OUTFILE, ">E:/Documents and Settings/Richard Lamb/My Documents/H
+TML/dummy.html") or die("$!: Can't write to the HTML file.\n");

while (<INFILE>)
{
    s/(<h[1-6]\s+style=.*)">/$1; word-spacing: 50px">/ig;
    s/(<li\sstyle=.*)">/$1; word-spacing: 20px">/ig;
    s/(<p style=.*)">/$1; word-spacing: 20px">/ig;
    print OUTFILE $_;
}
close (OUTFILE);
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