sed - remove nul lines from file
James B. Byrne
byrnejb at harte-lyne.ca
Tue Nov 7 18:54:45 UTC 2017
On Tue, November 7, 2017 13:36, Polytropon wrote:
> On Tue, 7 Nov 2017 12:12:55 -0500, James B. Byrne via
> freebsd-questions wrote:
>> I have a data file created by an ancient proprietary scripting
>> language called QTP. There is a bug in this program which, on
>> occasion, manifests itself by inserting output records consisting
>> entirely of nul (^@) (\x00) bytes at regular intervals. In the
>> present case every 47th. record consists entirely of nuls.
>
...
> In this case, awk can also help:
>
> $ awk '(length > 0)' < infile.txt > outfile.txt
>
> This will print all lines which are longer than 0 characters.
>
Thank you very much. This worked exactly as I required.
I infer from this that awk does not consider nul a character and its
presence does not count towards the length of a record. Which is
counter intuitive to me. A nul takes up the same space as any other
character so why is it not counted? I would not have tried this
construction for that reason.
--
*** e-Mail is NOT a SECURE channel ***
Do NOT transmit sensitive data via e-Mail
Do NOT open attachments nor follow links sent by e-Mail
James B. Byrne mailto:ByrneJB at Harte-Lyne.ca
Harte & Lyne Limited http://www.harte-lyne.ca
9 Brockley Drive vox: +1 905 561 1241
Hamilton, Ontario fax: +1 905 561 0757
Canada L8E 3C3
More information about the freebsd-questions
mailing list