[Shell] Running "breake 2" command from parametr for function

setevoy · 10-30-2013, 05:36 AM

Hello, people.

Have "simple" script.

In script has loop (cycle?) > function1 > if[...] > function2 > loop2.

function2 have second loop inside it:

Code:

function2 ()
    {
    while ... do
    ...
    done
    }

To end this sequence - function2 use $param4 with breake 2 command given in variable:

Code:

while function1; do
    ...
    function2 "$param1" "$param2" "$param3" "$param4
    ...
    done

And:

Code:

...
    param4="break 2"
    ...

Is it good idea - use so scheme? Is there any possible riskiness or something else "negative"?

Thanks fpor tips.

millgates · 10-30-2013, 06:14 AM

I'm not sure I understand what you're trying to do. Can you post a simple, but complete example?
That said, it is not a good idea to put commands into variables (see this)
Also, is the break 2 command actually supposed to break out of the function? That doesn't seem to me to be a good design either.

setevoy · 10-30-2013, 06:29 AM

Quote:

Originally Posted by millgates

That said, it is not a good idea to put commands into variables (see this)
Also, is the break 2 command actually supposed to break out of the function? That doesn't seem to me to be a good design either.

Thanks for link - it is really helpfull for me. Will read it later :-)

Quote:

I'm not sure I understand what you're trying to do. Can you post a simple, but complete example?

OK, here is full example.

Functions:

Code:

function answer ()
{
while read response; do
echo
case $response in
    [yY][eE][sS]|[yY])
        printf "$1\n"
        $2
        break
        ;;
    [nN][oO]|[nN])
        printf "$3\n"
        $4
        break
        ;;
        *)
        printf "Please, enter Y(yes) or N(no)! "
esac
done
}

Code:

function check_tomcat_status {
RUN=`ps aux | grep tomcat | grep -v grep | grep java | awk '{print $2}'`
}

Part of code where it's used:

Code:

printf "Checking Apache Tomcat status...\n\n"

while check_tomcat_status; do

if [ -n "$RUN" ]
then
printf "WARNING: Tomcat still running with PID $RUN. Stop it? "
answer "$tomcat_status_stoppping" "$tomcat_status_stop" "" "$tomcat_status_no"
sleep 2
        if [ -n "$RUN" ]
        then
                printf "WARNING: Tomcat still running. Kill it? "
                answer "$tomcat_status_stopping" "$tomcat_status_kill" "" "$tomcat_status_no"
                sleep 2
        fi
else
printf "Tomcat stopped, proceeding...\n\n"
break
fi

done

And variables:

Code:

tomcat_status_stop="/path_here/bin/shutdown.sh"
tomcat_status_stopping="Stopping Tomcat..."
tomcat_status_kill=". path_here/tom_kill.sh"
tomcat_status_no="break 2"

grail · 10-30-2013, 08:22 AM

Well not sure about anyone else but that seems even more confusing

Starting from the top down:

1. Look up case changing as no need to go through all those combinations for yes or no

2. Why not simply return the response from the loop and use a simple if to choose what to do

3. man pgrep - makes check_tomcat_status pointless

4. the point about placing commands in variables already pointed out and now we see not simply one but all 4 variables .. even sourcing from a variable. Maybe instead of using creative variable names in what seems to be an attempt to make the code something you can follow, simply add comments to your code