ERR trap
in [Shell]
|
Prev: download basics
Next: gnu-make prerequisites
From: John Kelly on 12 Aug 2010 16:27 Suppose I want to bail out of a script if any command exits with a non-zero status. AND, I want to know what line caused the problem. set -e will do it, but who knows what line aborted? trap 'echo $LINENO' ERR doesn't help either, because it reports the trap line, not what caused the trap. -- Web mail, POP3, and SMTP http://www.beewyz.com/freeaccounts.php
From: Eric on 12 Aug 2010 16:51 On 2010-08-12, John Kelly <jak(a)isp2dial.com> wrote: > > Suppose I want to bail out of a script if any command exits with a > non-zero status. AND, I want to know what line caused the problem. > > set -e > > will do it, but who knows what line aborted? > > trap 'echo $LINENO' ERR > > doesn't help either, because it reports the trap line, not what caused > the trap. > No it doesn't. trap "echo $LINENO" ERR would do that. Eric
From: John Kelly on 12 Aug 2010 17:38 On Thu, 12 Aug 2010 21:51:03 +0100, Eric <eric(a)deptj.eu> wrote: >On 2010-08-12, John Kelly <jak(a)isp2dial.com> wrote: >> >> Suppose I want to bail out of a script if any command exits with a >> non-zero status. AND, I want to know what line caused the problem. >> >> set -e >> >> will do it, but who knows what line aborted? >> >> trap 'echo $LINENO' ERR >> >> doesn't help either, because it reports the trap line, not what caused >> the trap. >> > >No it doesn't. > >trap "echo $LINENO" ERR > >would do that. #!/bin/sh trap "echo trap at $LINENO" ERR let x=0 let y=0 let z=0 # ./xs trap at 3 trap at 3 trap at 3 Nice try but no cigar. -- Web mail, POP3, and SMTP http://www.beewyz.com/freeaccounts.php
From: Seebs on 12 Aug 2010 18:52 On 2010-08-12, John Kelly <jak(a)isp2dial.com> wrote: > Suppose I want to bail out of a script if any command exits with a > non-zero status. AND, I want to know what line caused the problem. Oh, interesting. Have you considered also asking for a pony? :P > set -e > will do it, but who knows what line aborted? > trap 'echo $LINENO' ERR > doesn't help either, because it reports the trap line, not what caused > the trap. This surprises me, and I was about to give you the same answer you already got, but apparently that's wrong. However... #!/bin/sh trap 'echo error occurred on line: $LINENO' ERR set -e true false When I run this, I get: error occurred on line: 7 So I get the behavior we expected. Hmmmm. -s -- Copyright 2010, all wrongs reversed. Peter Seebach / usenet-nospam(a)seebs.net http://www.seebs.net/log/ <-- lawsuits, religion, and funny pictures http://en.wikipedia.org/wiki/Fair_Game_(Scientology) <-- get educated!
From: Seebs on 12 Aug 2010 18:54
On 2010-08-12, John Kelly <jak(a)isp2dial.com> wrote: > #!/bin/sh > > trap "echo trap at $LINENO" ERR > > let x=0 > let y=0 > let z=0 > > # ./xs > trap at 3 > trap at 3 > trap at 3 > Nice try but no cigar. Uh. Maybe you have a font problem? You have double quotes (") there, with which you get this behavior. I changed it to: trap 'echo trap at $LINENO' ERR and got: trap at 5 trap at 6 trap at 7 Eric's suggestion (use single quotes, aka apostrophes, rather than double quotes) appears to do exactly the right thing. Can you tell these apart on your display? ' (single quote) " (double quote) -s -- Copyright 2010, all wrongs reversed. Peter Seebach / usenet-nospam(a)seebs.net http://www.seebs.net/log/ <-- lawsuits, religion, and funny pictures http://en.wikipedia.org/wiki/Fair_Game_(Scientology) <-- get educated! |