Passing a variable from a child script back to the parent Post: 302199340

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Top Forums Shell Programming and Scripting Passing a variable from a child script back to the parent Post 302199340 by mstephens on Monday 26th of May 2008 04:32:58 PM

05-26-2008

Registered User

Quote:

Originally Posted by Andy82

Hi

I have written a script using ftp to get files from one server and copy them to 2 dirrerent servers. I wish to call this script from a parent script that will check the number of files copied and run a check sum for each file. As the filenames for the files in the get portion of the script are hard coded into the child script is it possible to pass these files names from the child back to the parent. I have seen some error checking examples but no examples of variable being passed back.

Any help would be greatly appreciated.

Andy, If you use ksh93 this will work.

Stick your child scripts into functions - or at least have functions which run the child scripts using the . operator so that they are running within the same process as the main script.

then do something like below:
------------------------------------------

function afunc
{
# This is the function which either contains the child script or calls it using # the . operator

# the line below makes parameter 1 a by reference parameter
typeset -n pFilename=$1
..
..
.. script sets vValue to a filename received by FTP somewhere in here
.. for example vValue="receivedfile.txt"
pFilename=$vValue

return 0
}

# The main script is here
..
..
..
# lets call the function
afunc vFilename
# note that vFilename = $1 in afunc and will point to the same memory address as pFilename variable in the function
echo $vFilename
# which miraculously will turn out to be "receivedfile.txt"
-------------------------------------------------------------

You could do something similar with ksh bash or sh but that would work because all the variables of scripts using the same process are global - some versions of bash may have ksh93 features though.

If you must use scripts which don't use the same processes then the following will work:

#---- Calling script--------
..
..
# call the child script
childscript.sh
avar=`cat afile`
echo $avar
..
..
#---end of calling script-------------------

#---childscript.sh---------------
..
.. bvar="receivedfile.txt" happens somewhere in here
..
echo $bvar > afile
#------ end of childscript.sh

mstephens

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LEARN ABOUT CENTOS

installsieve

INSTALLSIEVE(1) 					      General Commands Manual						   INSTALLSIEVE(1)

 *

NAME

       installsieve - user utility for managing sieve scripts

SYNOPSIS

       installsieve

DESCRIPTION

       installsieve is a utility that allows users to manage their sieve scripts kept on the server.

OPTIONS

       -v <name> View script with the given name. The script if retrieved sucessfully is output to standard output.

       -l  List  all  of  the scripts currently on the server. If one of the scripts is active a arrow is printed indicating that it is the active
       script.

       -p <port> Port to connect to. If left off this defaults to "sieve" as defined in /etc/services.

       -i <file> Install a file onto the server. If a script with the same name already exists on the server it is overwritten.  Upon  sucessfully
       putting	the  script on the server the script is set active. If <file> has the extension .script it is chopped when put on the server since
       sieve names may not contain a '.'.

       -a <name> Set <name> as the active script. The list of available names can be obtained from the '-l' option..

       -d <name> Delete the sieve script on the server with <name>.

       -m <mechanism> Force installsieve to use <mechanism> for authentication. If not specified the strongest authentication mechanism is chosen.

       -g <name> Get the sieve script with <name> and save it to disk with a ".script" extension. If a file with that name already  exists  it	is
       overwritten.

       -u <user> Userid/Authname to use for authentication; by default, the current user.

CMU
								   Project Cyrus						   INSTALLSIEVE(1)

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