"goto" equivalent in shell script

[Maciej Szewczykowski]

hello everybody,
my question is: is there an operation allowed in shell script language that has the same output as "goto" in C++? lets assume that i've written a command, its output is either 0 or 1, in case it's 1, i'd like to continue running the script from line of a certain number - that's what i need "goto" for.
thanks in advance.

[Geoff Wild]

several ways....you could do it with functions:

function task1{
echo "hello world"
done
}

##########################################################################
# Main Program #
##########################################################################

case $1 in

hello ) task1 ;;

esac

[T G Manikandan]

There is no equ. of goto in shell.

check for the 'break' statement which can be used for the same.

Thanks

[Maciej Szewczykowski]

thanks, but can you propose some other way to proceed it?

[John Meissner · Accepted solution]

I would use functions (as Geoff mentioned above)

function myfunction {
script stuff
}

while blah blah blah....
do
myfunction
done

if [ blah blah ]
then
myfunction
fi

you can call that same function at any time in the script which will work as a "goto" of sorts.

the case (as also mentioned above) will let you do a similar thing as the function... but call various things.... I use this when creating a menu in a script.
The below excert from one of my scripts is written as a function... but also has a case statement used.

function user_grp {
clear
echo " Enter the user you wish to assign to a group:\c"
read user
clear
echo " Assign $user into a group"
echo " ${BOLD}1${NORMAL} - ART-ISC"
echo " ${BOLD}2${NORMAL} - GTS"
echo " ${BOLD}3${NORMAL} - SAP"
echo " ${BOLD}4${NORMAL} - Telecoms"

until [ "$group" = "1" ] || [ "$group" = "2" ] ||
[ "$group" = "3" ] || [ "$group" = "4" ] ; do
echo "Please select one of the menu options"

read group
done
case $group in
1)
grp=ART-ISC
;;
2)
grp=GTS
;;
3)
grp=SAP
;;
4)
grp=Telecoms
;;
esac
echo "$user:$grp:n:*" >> ~/scmauth/auth
mxauth -a -f ~/scmauth/auth
echo "authorization complete"
echo "$user added to $grp on all servers"
echo "$user was added to $grp on all servers by `logname` on `date` " >> ~/scmauth/auth.added.log
more auth >> auth.granted
rm auth
touch auth
sleep 5
~/scmauth/scm_menu
}

[Darren Prior]

Hi,

Although there may be a goto statement it's not a particularly nice way to program!

How about something like:

your_user_command
if [[ $? -eq 0 ]]
then
do stuff for command outputting 0
else
do stuff for command outputting 1
fi

or you could use functions to separate it out. You may need to rethink the script; but it will be more structured and easier to follow.

regards,

Darren.

[John Meissner]

dating back to my Basic programming class I took - goto is used to go to a specific line number. probably more advanced now - but that's what I remember. Scripting uses logic and flow control to process such things.... if then statements.... functions.... variables..... exit codes.... case statements....
There is a bit to learn to change the way you approach this problem. That's why we're here :) glad to help with any scripting questions you may have.

[Maciej Szewczykowski]

great thanks john, thank you all guys.

[Steve Steel]

Hi


Strange thing with scripting.

. script

Will not fork but continue at the same level.

Thus you can even


if [[ $? -eq 0 ]]
then
. scriptres0
else
. scriptres1
fi

And insert small scripts into your script depending on the result.


Steve Steel