shell script in android gives [: not found

Question

I have this script which works on my linux machine

#!/bin/sh
c=1
if [ $c == 1 ]
then
  echo c is 1
else
  echo c is 0
fi

But when I use this in

Answer 1

Android does not provide a full UNIX environment, it is not a UNIX operating system. It has some similarities, much like how Windows also has some similarities to UNIX. Some Android devices and ROMs try to provide more of a UNIX-like environment that others, but you cannot rely on most of the standard shell scripting tools being installed if you are thinking about cross-device compatibility.

So for example, if you look at your GNU/Linux system, you can see that test and [ are actually programs. Try this: ls -l /usr/bin/[. Most Android installs do not include test or [. That means that if you want to try to do actual programming with Android's minimal shell environment, you have to use lots of odd tricks. You can install busybox to get a full UNIX shell environment, or you can even build busybox into your app. I do that when I need to include shell scripts in an app (for example, Lil' Debi and Commotion MeshTether).

Here's an example of writing a killall in Android's /system/bin/sh environment: http://en.androidwiki.com/wiki/Android_Shell_tips_and_tricks You can also use the various parameter expansions to create some logic, you can see an example of that in the Barnacle Wifi Tether scripts.