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1. Embed this notice
   ploum (ploum@mamot.fr)'s status on Friday, 29-Nov-2024 20:07:02 JST ploum

   Dear #python and #unix hackers,

   I’m trying to find out, in Python, if "grep" has the option "--color=auto" or not.

   (to make #offpunk compatible with #openbsd grep )

   Any suggestion? (the one on the mailing-list doesn’t work for me)

   I could simply scan "grep --help" for the option but, intuitively, I don’t like it.

   https://lists.sr.ht/~lioploum/offpunk-devel/%3CD5XQC1ECYEID.3KHOCET4CTSM0@dsilva.email%3E

   • Embed this notice
     Solène :flan_hacker: (solene@bsd.network)'s status on Friday, 29-Nov-2024 20:47:28 JST Solène :flan_hacker:

     in reply to

     • Marcos Dione

     @mdione @ploum this is the best option in my opinion, you won't have to write a compatibility table depending on which version will run, by checking this way, you will always have the right result.

   • Embed this notice
     Marcos Dione (mdione@en.osm.town)'s status on Friday, 29-Nov-2024 20:47:30 JST Marcos Dione

     in reply to

     @ploum run the command with the option and check whether the exit code is not 0?

   • Embed this notice
     ploum (ploum@mamot.fr)'s status on Friday, 29-Nov-2024 21:24:38 JST ploum

     in reply to

     • Ingo van Lil

     @inguin : you saved me ! I missed the "b" in the input and thus I was always having errors.

   • Embed this notice
     Ingo van Lil (inguin@nerdculture.de)'s status on Friday, 29-Nov-2024 21:24:39 JST Ingo van Lil

     in reply to

     @ploum I would call the command with the option and see if it works:

     status = subprocess.run(["grep", "--color=auto", "x"], input=b'x')

     If status.returncode is zero the option is supported (or at least tolerated).

   • Embed this notice
     ploum (ploum@mamot.fr)'s status on Friday, 29-Nov-2024 23:03:52 JST ploum

     in reply to

     • tnt

     @tnt : that’s quite error prone (need to check the path).

     I managed to do it by checking for "x" in the binary stream b'x' with the color option. If it fails, fallback to grep without color. (the challenge was to ensure that the grep test would succeed)

   • Embed this notice
     tnt (tnt@chaos.social)'s status on Friday, 29-Nov-2024 23:03:54 JST tnt

     in reply to

     b'color' in open('/bin/grep','rb').read() ?