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Full Discussion: VM trap may work differently than a pure install trap.
Homework and Emergencies Homework & Coursework Questions VM trap may work differently than a pure install trap. Post 302809621 by bakunin on Monday 20th of May 2013 09:21:27 AM
Old 05-20-2013
Quote:
Originally Posted by newuser45
Code:
#! /bin/bash
count=1
trap " echo 'I have trapped CTRL-C'" SIGTERM SIGINT
echo "Start of the program..."
while [ $count -lt 10 ]
        do
        echo "Loop #$count"
        sleep 10
        count=$[ count + 1]
        done
echo "End of the program..."

I pasted the quoted code into a file and ran it and - to my surprise - it worked. I would have expected this:

Code:
        count=$[ count + 1]

to caue problems, it "just doesn't seem right", but then, i use Korn Shell most of the times and avoid bash like the plague. I would have written:

Code:
        (( count += 1 ))

which should do the same and is POSIXly correct (notice the spaces around "((" and "))", they are necessary), but: never argue with success, yours obviously works.

One thing i noticed, though, was: as soon as i pressed "CTRL-C" the trap was executed but the "sleep 10" was interrupted and then skipped. Pressing CTRL-C often enough let me get through with the script in less than half a minute, whereas 10x 10 seconds of sleeping should have taken 1min 40sec (plus some for the rest).

So, probably there is something with your setup. I have no idea what that would be, though. I tried in an XTerm on Fedora without any real changes and it worked as expected.

I hope this helps.

bakunin
 

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LEARN ABOUT V7

debconf-mergetemplate

DEBCONF-MERGETEMPLATE(1)					      Debconf						  DEBCONF-MERGETEMPLATE(1)

NAME

       debconf-mergetemplate - merge together multiple debconf template files

SYNOPSIS

	debconf-mergetemplate [options] [templates.ll ...] templates

DESCRIPTION

       Note: This utility is deprecated. You should switch to using po-debconf's po2debconf program.

       This program is useful if you have multiple debconf templates files which you want to merge together into one big file. All the specified
       files will be read in, merged, and output to standard output.

       This can be especially useful if you are dealing with translated template files. In this case, you might have your main template file, plus
       several other files provided by the translators. These files will have translated fields in them, and maybe the translators left in the
       english versions of the fields they translated, for their reference.

       So, you want to merge together all the translated templates files with your main templates file. Any fields that are unique to the
       translated files need to be added in to the correct templates, but any fields they have in common should be superseded by the fields in the
       main file (which might be more up-to-date).

       This program handles that case properly, just list each of the translated templates files, and then your main templates file last.

OPTIONS

       --outdated
	   Merge in even outdated translations. The default is to drop them with a warning message.

       --drop-old-templates
	   If a translation has an entire template that is not in the master file (and thus is probably an old template), drop that entire
	   template.

SEE ALSO

       debconf-getlang(1)

AUTHOR

       Joey Hess <joeyh@debian.org>

								    2012-09-10						  DEBCONF-MERGETEMPLATE(1)
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