It's better if you can work out how to do this on your own by reading the sources mentioned above. Here is some example code, although much of it may still be confusing without doing some additional reading:

# Set the input and output filenames
my $ifilename = 'file.in';
my $ofilename = $ifilename . '.bin';

# Open the files and ensure we handle them as binary data
open my $ifile, '<', $ifilename or die "could not open input file $!";
open my $ofile, '>', $ofilename or die "could not open output file $!"
+;
binmode $ifile;
binmode $ofile;

# Read the binary data
$_ = do { local $/; <$ifile> };

# Replace the initial bytes with zero
s/^(.*?)(\x4F\xFF)/"\x0" x length($1) . $2/se;

# Store the result in the output file
print $ofile $_;

# Tidy up
close $ifile;
close $ofile;

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In reply to Re: how to read binary file and give a binary output? by Loops
in thread how to read binary file and give a binary output? by perllearn

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