in reply to Null \x00 being replaced by space \x20

Hello BaldGorilla, and welcome to the Monastery!

I assume the line print $new_gpd_fh "$line"; is meant to be print $new_fh "$line";? With this change made, I cannot reproduce your problem.

Specifically, I created a text file, then used a hex editor to insert a null (\x00) at a suitable place in the text, and ran the script. The resulting new file has a null character in the correct place, as expected. (Confirmed both in the hex editor and in Notepad++, which displays a NUL control character.)

Are you sure that your new file contains a space character in place of the null? Or could the space you are seeing be an artefact of the way you are viewing the file contents?

Cheers,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

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Re^2: Null \x00 being replaced by space \x20
by BaldGorilla (Initiate) on Nov 10, 2018 at 04:18 UTC
    Yes, fixed the the typo, sorry about that. I'm using UltraEdit and Notepad++ and I see the null and space difference. Is there any way to send screen shots?
[reply]
      Is there any way to send screen shots?

      Better just to get perl to tell you what's in the file.
      As Athanasius suggested, I suspect that the file really does contain a NULL, and the tool you're using to look at it converts it to a space.

      On Windows 7 (perl-5.28.0), I created a file (null.txt) by running: 
      C:\_32> perl -e "$s = 'x' . chr(0) . 'y';print $s;" >null.txt

      [download]
      I then examined the contents of null.txt by running: 
      C:\_32> perl -le "open RD, '<', 'null.txt'; $x = <RD>; chomp $x; print
+ ord substr($x, 0, 1); print ord substr($x, 1, 1);print ord substr($x
+, 2, 1); print length $x;"
120
0
121
3

      [download]
      After using your script to create null.txt.new, I then ran the same one liner to ascertain the contents of null.new.txt 
      C:\_32> perl -le "open RD, '<', 'null.txt.new'; $x = <RD>; chomp $x; p
+rint ord substr($x, 0, 1); print ord substr($x, 1, 1);print ord subst
+r($x, 2, 1); print length $x;"
120
0
121
3

      [download]
      So it looks to me that I also am unable to reproduce the problem.

      Cheers,
      Rob
[reply]
[d/l]
[select]
        It was an issue with the text editor converting it to a space. Thank you all for the assistance!
[reply]

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