On a 2GB/5.7 million line file, it consistently runs in 30-35 seconds on my AS1007 perl: 

[20:14:52.61] C:\test>dir 834245.masks
 Volume in drive C has no label.
 Volume Serial Number is 8C78-4B42

 Directory of C:\test

18/04/2010  01:02     2,412,431,484 834245.masks
               1 File(s)  2,412,431,484 bytes
               0 Dir(s)  296,257,802,240 bytes free

[20:16:19.67] C:\test>perl -ne "s/\x00\x42\x00\x11/\x00\x42\x00\xf0/sg
+" 834245.masks >junk.dat

[20:16:55.62] C:\test>

[download]

Which is only a few seconds longer that wc -l takes to just count the lines.

How long does your SP 5.12 take?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
RIP an inspiration; A true Folk's Guy

In reply to Re: Slow find/replace hex in Perl win32 by BrowserUk
in thread Slow find/replace hex in Perl win32 by rickyboone

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