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Re: bash, sed, SIGPIPE
From: |
Eric Blake |
Subject: |
Re: bash, sed, SIGPIPE |
Date: |
Thu, 01 Jan 2009 17:25:20 -0700 |
User-agent: |
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.19) Gecko/20081209 Thunderbird/2.0.0.19 Mnenhy/0.7.5.666 |
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According to Bruno Haible on 1/1/2009 5:09 PM:
> After 'trap - SIGPIPE', sed should get a fatal SIGPIPE signal in these
> conditions.
> Quoting
> <http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#trap>
>
> "If action is '-' , the shell shall reset each condition to the default
> value."
You're missing one other piece.
"Signals that were ignored on entry to a non-interactive shell cannot be
trapped or reset, although no error need be reported when attempting to do
so."
Therefore, if a bash script is started while SIGPIPE is already ignored,
there is nothing the script can do to turn it off ('trap - SIGPIPE' only
re-enables default behavior if your script was the one that disabled it in
the first place, but not if your script started with it already disabled).
- --
Don't work too hard, make some time for fun as well!
Eric Blake address@hidden
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- Re: sed, SIGPIPE, cmp -s [Re: [PATCH 3/4] gnulib-tool: abort loops early where possible., Bruno Haible, 2009/01/01
- Re: sed, SIGPIPE, cmp -s [Re: [PATCH 3/4] gnulib-tool: abort loops early where possible., Jim Meyering, 2009/01/01
- Re: bash, sed, SIGPIPE, Bruno Haible, 2009/01/01
- Re: bash, sed, SIGPIPE,
Eric Blake <=
- Re: bash, sed, SIGPIPE, Bruno Haible, 2009/01/01
- Re: bash, sed, SIGPIPE, Jim Meyering, 2009/01/02