On: Use long flags when scripting

[lamby]

> Will this script ever run anywhere that I don't have the GNU toolchain? Effectively-0% likely.

Not really. A lot of stuff broke when /bin/sh moved to a POSIX-compatibile shell rather than Bash.

[njharman → lamby]

No a lot of stuff broke because people depended on implicit rather than being explicit.

    #!/bin/bash

[Wilya → njharman]

  wilya@home $ /bin/bash
  zsh: no such file or directory: /bin/bash
  wilya@home $ which bash
  /usr/local/bin/bash

(Yes, I'm annoyed when I see #!/bin/bash, especially on scripts which are otherwise basic enough to be portable everywhere)

[dfox → Wilya]

It is still better to write #!/bin/bash for bashism using scripts than #!/bin/sh. I recently had to run sed -i (well, another GNUism) 1s%/sh%/bash% on bunch of customer's scripts to make them work on debian. At least when script wants /bin/bash it is going to fail cleanly (and not in the middle after modifying random things) and with mostly meaningful error.

[wollw → njharman]

It's probably safer to use:

    #!/usr/bin/env bash

Assuming env is installed (I believe I had to install a package on OpenBSD to use it) this will find the first instance of bash in the PATH.

[atsaloli → wollw]

How do you know env is in /usr/bin rather than in /bin or /usr/local/bin? I'm just curious...

[wollw → atsaloli]

You don't, but I've run into more problems with bash being in unexpected places than env.

[atsaloli → wollw]

Right on, thanks.

[ralph → atsaloli]

Good question. I've used systems, e.g. AIX, where env(1) was in /bin.