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From: Kaz Kylheku <046-301-5902@kylheku.com>
Newsgroups: comp.lang.awk
Subject: Re: Can I output a binary file from an AWK program?
Date: Sun, 29 Mar 2026 23:45:18 -0000 (UTC)
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On 2026-03-28, Alan Mackenzie <acm@muc.de> wrote:
> I think the Subject: line says it all.  I have a text source file to
> convert into a binary output file.  For example, I want to be able to
> output a 32-bit integer as a four byte little-endian binary integer.

Firstly, Awk's printf has a %c specifier which will output any byte:

$ awk 'BEGIN { printf("%c%c", 0x41, 0x0A) }'
A
$

Another idea is to output a textual dump compatible with xxd.
(xxd == fairly widely installed utility that comes with Vim).
xxd can revert xxd dumps back to binary:

$ xxd /etc/bash_completion
00000000: 2e20 2f75 7372 2f73 6861 7265 2f62 6173  . /usr/share/bas
00000010: 682d 636f 6d70 6c65 7469 6f6e 2f62 6173  h-completion/bas
00000020: 685f 636f 6d70 6c65 7469 6f6e 0a         h_completion.
$ xxd /etc/bash_completion | xxd -r
. /usr/share/bash-completion/bash_completion

IIRC there is a bit of tolerance in "xxd -r". Indeed:

$ xxd -r
0: 41 57 4B 0A
AWK
0: 42 494E 0A
BIN