UNIX for Dummies Questions & Answers

Hi everyone.

Code:

#!/sbin/sh

EXITING()
{
        umount /FOLDER
        rm -Rf /FOLDER 
        echo "EXIT"
        exit 0      
} 


EXITING 

echo "OK"

This is my stripped script for android environment and is launched in the recovery mode. No bash or ksh, must be /sbin/sh provided and symlinked by busybox toolbox.

When function is called, the commands "exit", "exit 0" and "exit 1" only exit from function and always show "EXIT" and "OK", but not end the script as I would like. Whats wrong?

I need call EXITING many times in the script and need the "exit" command working, is there an alternative to force exit?

thank in advance and sorry for my english.

I cannot reproduce this using busybox 1.17.1

I'm using busybox "BusyBox v1.19.4-cm9 bionic" included in the cyanogenmod 9 kernel.

I'm pretty sure that in others kernels/busybox this code is working flawless but I need to find an universal method that provide an exit in whatever busybox version.

If you are looking to do cleanup on script exit, maybe you really want just trap:

Code:

cleanup() {
    rm ... etc ...
}
trap cleanup EXIT

but no matter what I do, exit has always exit the script... maybe is issue elsewhere in script? this small snippet alone reproduces "OK" for you ?

Ok I've found the problem.

When EXITING is called from a "for-done" loop doesn't work and only break it.
But if I call it in other situation works fine.

Is it a normal behavior? For future referencies...

Thanks for the help

No... Seems like behavior of break. Are you sure /sbin/sh is busybox's? Seems like an odd place. Thought Android put it in /system/xbin or something. It may have -x option to trace. if you run sh -x script you should see nothing after + exit ...

mmmm I know, but it happens.

OK, my fault, sorry, EXITING is called from other function, this is the problem.

the "for" loop call "CHECKING" and then call "EXITING" , but only break the "for" loop, and get the same behavior, show me "OK" echo.

(*this is a sample to show the concept)



test.sh

Code:

#!/sbin/sh

CHECKING()
{
	EXITING 0
}



EXITING()
{
        exit 0      
} 



for i in ls ;do
  ls *.tar* | while read i;do
      echo "Hello"
      CHECKING
  done
done

echo "OK"

sh -x test.sh

Code:

/emmc # sh -x test.sh
+ sh -x test.sh
+ read i
+ ls Backup.tar p7zip.tar.bz2
+ echo Hello
Hello
+ CHECKING
+ EXITING 0
+ exit 0
+ echo OK
OK

I use "#!/sbin/sh" because my script in some point makes a /system format and need the busybox integrated in the recovery, not the included in /system. And /sbin/sh is the standard path to launch the shell from recovery.