<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div>It's basically making sure you are in the directory the script resides in, whether you run it from that directory or another. <br><br><span style="font-size: 13pt;">Geoffrey Myers</span></div><div><br>On Mar 11, 2014, at 1:42 PM, Jonathan Meek <<a href="mailto:jonathan.l.meek@gmail.com">jonathan.l.meek@gmail.com</a>> wrote:<br><br></div><blockquote type="cite"><div><div dir="ltr">Hello everyone, <div><br></div><div>I am reviewing a script at work in order to understand that someone has done before me. They decided to ksh to write their scripting. There's an if statement I don't quite get and would be grateful for some light on the issue. Here's the code snippet: </div>
<div><br></div><div><div><font face="courier new, monospace">if [ ${0#/} = ${0} ] ; then</font></div><div><font face="courier new, monospace"> X=${PWD}/${0}</font></div><div><font face="courier new, monospace"> else</font></div>
<div><font face="courier new, monospace"> X=${0}</font></div><div><font face="courier new, monospace"> fi</font></div><div><font face="courier new, monospace"> cd $(dirname ${X})</font></div></div><div><font face="courier new, monospace"><br>
</font></div><div><font face="arial, helvetica, sans-serif">Based on my own searching for meaning and understanding and somewhat limited look into the man pages for ksh(couldn't remember how to search within vi), here's what I think is going on:</font></div>
<blockquote style="margin:0 0 0 40px;border:none;padding:0px"><div><font face="arial, helvetica, sans-serif">The if statement is checking what shell is currently running and as long as it is the expected shell, it will assign X to ${PWD}/${0}. If not, it will assign X to ${0}. Then it will change directories based on the output of dirname, which could be the current directory or the directory that variable X is at. </font></div>
</blockquote><div><font face="arial, helvetica, sans-serif"><br></font></div><div><font face="arial, helvetica, sans-serif">Does this sound right or I am missing something? </font></div><div><font face="arial, helvetica, sans-serif"><br>
</font></div><div><font face="arial, helvetica, sans-serif">Regards, </font></div><div><font face="arial, helvetica, sans-serif"><br></font></div><div><font face="arial, helvetica, sans-serif">Jonathan</font></div></div>
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