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Re: [zsh] How to mimic errexit within subshell (or function)?

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2012-05-02 19:33:34 +0000, kj:
[...]
> >I personally wouldn't touch "set -e" with a barge pole,
> 
> 
> *gulp*, that's really bad news, since I have 'set -e' all over my
> scripts...
> 
> I just searched for "set -e" bugs for zsh online, and found only
> a couple of (sufficiently distinct-looking) hits:
> 
>   http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=520101
>   http://permalink.gmane.org/gmane.linux.debian.devel.bugs.general/545456
> 
> Is this what you have in mind?
[...]

No, that's about coding practice, maintainability and
reliability.

Relying on "set -e" to do your error handling is a bad idea in
anything more than the simplest of scripts that just run a
command after the other.

- commands can have non-zero exit statuses that don't mean an
  error (see "test", "expr", "grep"...)
- subtleties like the one you discovered about where its effects
  are cancelled
- interactions with subshells, pipes, background jobs
- some commands will output errors, some will no, "set -e" will
  not explain why the script dies.

You just can't assume it works without having to worry.

And if you start to worry, it's a lot simpler to do the error
handling properly.

That's my opinion anyway.

-- 
Stephane
- 

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Thread

[zsh] How to mimic errexit within subshell (or function)? kj <no.email@please.post> - 2012-05-01 21:20 +0000
  Re: [zsh] How to mimic errexit within subshell (or function)? Stephane Chazelas <stephane.chazelas@gmail.com> - 2012-05-02 07:34 +0100
    Re: [zsh] How to mimic errexit within subshell (or function)? Geoff Clare <geoff@clare.See-My-Signature.invalid> - 2012-05-02 13:51 +0100
      Re: [zsh] How to mimic errexit within subshell (or function)? Stephane Chazelas <stephane.chazelas@gmail.com> - 2012-05-02 14:29 +0100
    Re: [zsh] How to mimic errexit within subshell (or function)? kj <no.email@please.post> - 2012-05-02 19:33 +0000
      Re: [zsh] How to mimic errexit within subshell (or function)? Stephane Chazelas <stephane.chazelas@gmail.com> - 2012-05-02 20:53 +0100
  Re: [zsh] How to mimic errexit within subshell (or function)? Martin Vaeth <vaeth@mathematik.uni-wuerzburg.de> - 2012-05-02 10:30 +0000
    Re: [zsh] How to mimic errexit within subshell (or function)? kj <no.email@please.post> - 2012-05-02 19:09 +0000
      Re: [zsh] How to mimic errexit within subshell (or function)? kj <no.email@please.post> - 2012-05-02 19:12 +0000
      Re: [zsh] How to mimic errexit within subshell (or function)? Stephane Chazelas <stephane.chazelas@gmail.com> - 2012-05-02 20:27 +0100
        Re: [zsh] How to mimic errexit within subshell (or function)? kj <no.email@please.post> - 2012-05-03 18:20 +0000

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