Need some help with a bash script Post: 302990948

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Homework and Emergencies Homework & Coursework Questions Need some help with a bash script Post 302990948 by Eggsy on Friday 3rd of February 2017 09:10:25 AM

02-03-2017

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Thanks for your answer. Would you mind helping me to understand how exactly those statements work then.

Is my assumption that "grep s>/dev/null" and "grep r>/dev/null" check whether or not a filename contains an S and an R correct?

So looking over it again, for 2. would this mean it's invoked 15 times too, because it checks every single file.
And as for 3. could it be 7 times, since you only reach the "grep r>/dev/null" part when it found an S in the name (since there are only 7 files with an S)?

---------- Post updated at 09:10 AM ---------- Previous update was at 09:02 AM ----------

Quote:

Originally Posted by RudiC

Welcome to the forum.

As to your questions:

May I question your reasoning?
a) Where in the script are S or R to be matched? Both upper case?
b) Do you know the meaning of the || operator in shell scripts?

1. How many input items do you have? And, how is the end-of-file detected?
2. Once in the loop, how many times do you think the commands or lists will be executed?
3.and
4. Again: Do you know the meaning of || in shell scripts? How would it influence the execution of the command list?
5. Correct!

a) I believe the filenames were actually all lower case. (As a german, we capitalize names, so that was my mistake when I wrote this down)

b) || means we only reach the right side, when the left side is true, iirc. So once it found a filename with an "s", it checks for an "r"?

1. We have 15 items. So it goes through the list of files until every single one was checked?
2. Also 15 times, since it checks every single item for an "s"?
3. 7 times, since we only reach the second part, when we found an item with an "s"
4. 3 times, since we only reach that part, when we found an item with an "s" and an "r"

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LEARN ABOUT SUSE

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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