Use long flags when scripting (2013)

Post by gkop » Fri, Sep 18, 2020, 6:05 PM UTC

adrianmonk wrote: post #19

Great suggestion, but I'd go for a middle ground: use long flags for the long tail, but short flags are fine for stuff that's very commonly used. I think I'll continue to write these: grep -i rm -rf ln -s gzip -v sed -e instead of: grep --ignore-case rm --recursive --force ln --symbolic gzip --verbose sed --expression If you're working on shell scripts, you probably know certain short flags well enough that long flag…

Post by samtheprogram » Fri, Sep 18, 2020, 6:07 PM UTC

Analemma_ wrote: post #6

jwmhjwmh wrote: post #2

If you're trying to stick to the POSIX standard, you have to use short options for standard commands like grep, since the long options are GNU extensions.

Unless you count things like Makefiles, I don't think I've ever written or encountered a "script" that was intended for use on multiple *nix flavors. This strikes me as a YAGNI situation: do it if it comes up, but not before.

Post by periodontal » Fri, Sep 18, 2020, 6:12 PM UTC

inshadows wrote: post #14

m463 wrote: post #3

In scripts, I usually do stuff like this command \ --longopt1 \ --longopt2 arg \ argument or command | \ command 2 | \ command 3 \ --opt1 \ --opt2 \ arg

It's nice but you cannot comment individual lines. For that you can go one step further and use arrays: cmd=( command -x -y --bar OPTARG ARG ARG ) $cmd This works in Zsh. In Bash that would be ${cmd[@]} I think. I use this with long qemu command lines where I often modify and comment out arguments during testing.

  cmd=(
   test
   "!= !="
   !=
   ""
  )
  "${cmd[@]}" && echo Success
  ${cmd[@]} || echo Failure

Post by kazinator » Fri, Sep 18, 2020, 6:14 PM UTC

lhoursquentin wrote: post #10

Analemma_ wrote: post #6

Earlier quoted context omitted.

Unless you count things like Makefiles, I don't think I've ever written or encountered a "script" that was intended for use on multiple *nix flavors. This strikes me as a YAGNI situation: do it if it comes up, but not before.

Yes most of the time the respecting POSIX to the letter is not needed, but it is of course satisfying knowing that your script can run fine on BSDs and other less common distributions :) Though sometimes you don't need to go that far to break stuff, for instance switching from Fedora to Ubuntu. I've seen many scripts fail on debian derivatives because people think using #!/bin/sh as a shebang is fine since it works o…

Post by makecheck » Fri, Sep 18, 2020, 6:24 PM UTC