Extension Attribute script logic help

Steve,

Thanks for the help.

Here is the updated version. This does the trick.

#!/bin/bash
ls -alh /Library/Security/ | grep PolicyBanner
if [ "$?" = 0 ] then echo "<result>Yes_PolicyBanner</result>"
else echo "<result>No_PolicyBanner</result>"
fi

Don't make a habit of parsing ls. Also, there are much better ways to test if something exists etc.

This is what you want:

#!/bin/bash

if [[ -e /Library/Security/PolicyBanner.txt ]]; then
    echo "<result>Yes_PolicyBanner</result>"
else
    echo "<result>No_PolicyBanner</result>"
fi

And if you truly do not know if it will be a .txt, .rtf, or an .rtfd and you don't care then this will tell you if anything called PolicyBanner exists

#!/bin/bash

shopt -s nullglob
bannerfiles=(/Library/Security/PolicyBanner.*)

if [[ ${#bannerfiles[@]} -gt 0 ]]; then
    echo "<result>Yes_PolicyBanner</result>"
else
    echo "<result>No_PolicyBanner</result>"
fi

Why you shouldn't parse the output of ls(1)
http://mywiki.wooledge.org/ParsingLs

Tests and Conditionals
http://mywiki.wooledge.org/BashGuide/TestsAndConditionals

Also, for future cases where you really need it grep -q will do what you were kinda trying to do by checking the exit status.

Start Here.
http://mywiki.wooledge.org/BashGuide

The LDP "Bash Guide for Beginners" and ABS aren't the greatest.

Yes, bash has a lot of built in functions to check if files exist, if something is a directory, if it is a file and so forth. These require less code and run with in the shell itself, so they should technically also be more efficient.

YEP!

mine run in .006 and .007 seconds respectively. The one with the "| grep" takes .012!

lol. :D

In all seriousness though spawning subshells, using pipes and external programs will add up in really big scripts. They also tend to be more fragile.

Haha, but hey you'll never get those 0.05 seconds back!

This thread helped me figure out building an extension attribute I needed in a rush, thanks for posting.