HOW DO I RUN A UNIX BASH SCRIPT FROM JAVA??

Question

HI. Here's a tricky little problem i have. There's a unix bash script that has some commands in it, that manipulate a file. It appends a certain string variable to a file called users. The users file is an ordinary text file.
I know this script to work perfectly, when i invoke it like this directyl from the command line: ./addusers.sh
or even: bash /downloads/selinux/policy/addusers.sh
Now, i have a java program, and its meant to just execute that script. It doesnt throw any Exceptions at runtime. But when i look at the users file, and expect it to have an extra line that was the string variable, the file is UNTOUCHED!
Again, direct command line invocation works, but not from java. Here's what my invocation from java looks like:
Process p = Runtime.getRunTime().exec("bash downloads/selinux/policy/addusers.sh");
The strange thing is, i tried a different bash command. I tried:
Process p = Runtime.getRunTime().exec("mkdir /temporary");
and this worked!
so why not the other one??
I cant figure it out.

Answer 1

You say:
bash /downloads/selinux/policy/addusers.sh
And you say in Java:
Process p = Runtime.getRunTime().exec("bash
downloads/selinux/policy/addusers.sh");
As if a leading / would be missing from the Java
version...nyix says:>
...OK sorry about that. i DO have a / in front of the downloads.... section in the java method. So its:
Process p = Runtime.getRunTime().
exec("bash /downloads/selinux/policy/addusers.sh");
HELP please?