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Top Forums Shell Programming and Scripting what does this piece of code do? Post 302075599 by Vikas Sood on Monday 5th of June 2006 03:59:27 PM
Old 06-05-2006
what does this piece of code do?

Hi All,

I am trying to understand and change some code written by some programmer a while ago. There are following three lines of code that I am unable to grasp. Could anybody please help me understand it?

1) cd - > /dev/null

2) fname=`basename "$1"` where $1 = /dirA/dirB/a.txt
dname="${1%/$fname}"

I understand in this case fname would give me a.txt but what will dname be? I tried to echo dname on command line but it comes out to be blank

3) var1=/xx/yy
var2=${var1##*/}1

The result of the above is yy1. How does var2 get set to yy1?

4) inUse=`fuser "$1" 2>&1`
outputLines=`cat <<! | wc -l
${inUse}
!`

What I dont understand in above code is, if the intent of the programmer is just to count the number of rows returned by inUse variable, why did she choose to have <<! ?? Is there a good reason behind it or is just too complex without any good reason?

Thanks guyz.

Last edited by Vikas Sood; 06-05-2006 at 05:07 PM..
 

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SHUNIT2(1)																SHUNIT2(1)

NAME
shunit2 - A unit test framework for shell scripts SYNOPSIS
shunit2 unitfile DESCRIPTION
shUnit2 is a xUnit unit test framework for Bourne based shell scripts, and it is designed to work in a similar manner to JUnit, PyUnit, etc.. If you have ever had the desire to write a unit test for a shell script, shUnit2 can do the job. You can either run shunit2 directly from the commandline and specify the unit file or directly source the shunit2 executable. If you directly execute shunit2 and don't specify a unitfile shunit2 assumes a empty testfile and will return without an error message. EXAMPLE
Simple script to test if 1 equals 1 #! /bin/sh testEquality() { assertEquals 1 1 } # load shunit2 . shunit2 Execute shUnit2 unit tests directly from the commandline shunit2 /path/to/unit/file OPTIONS
shunit2 does not support any commandline options at all. You can either source shunit2 to execute your unit tests or directly run shunit2 as a commandline script. SEE ALSO
For more information see http://code.google.com/p/shunit2/ or have a look at the installed documentation in /usr/share/doc/shunit2/ AUTHOR
shunit2 was written by Kate Ward <kate.ward@forestent.com>. This manpage was written by Ulrich Dangel <mru@spamt.net>. 2.1.6 03/25/2012 SHUNIT2(1)
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