Shell Programming and Scripting

I have this shell script and in case the sybase process is been killed how can identify whether the process was killed or not, as the error code always returns 0.

Code:

#!/bin/sh
isql -S  SERVER -U user -P pass<<TOP
select * from tableName
go
TOP

echo $?

Cmd can make own signal handling and then make own exit codes. So you must search answer from isql documentation.

Also it's easy to test something like:

Code:

isql ...
echo "stat:$?"
echo ""

Run script in background, look cmd process id, sent some signals.

Code:

./script &
ps -f | grep isql
# look isql PID and test it:
kill -3  isqlPID
kill isqlPID
...

Ex. I tested in my own system what is value of exit status if my cmd is find.
Exit code tell the interrupt signal (exitcode - 256 = signal). Also kill -9.

That would only help in case of script getting killed what if the select statement is killed from database.