Calling functions in scripts directly

Shell Programming and Scripting
1

Hi,

I have a menu driven script that does various tasks, I want to be able to call functions directly from within other unix scripts from my menu script. Is this possible?

2

Its possible. Just make sure that the function is defined before its called.

3

How do you do it ranj? What do you mean about path names? Could you give me an example?

Thanks

4

Can you tell exactly what you are trying to achieve?

5

Bascially i have a menu:

doSQLSubMenu()
{
while true
do
showSQLSubMenu

 read answer

 MSG=

 case $answer in
    1\) ;;
    2\) ;;
    3\) ;;

    r|R\) break;;

    *\) badChoice;;
 esac

done
}

I want to make calls functions within different .sh scripts for option 1,2 and 3.

So say i had a function view() in a.sh

I would ideally want if you pressed 1 to call a.view()

Then another script perhaps b.sh

So if you pressed 2 it would call b.<function_name>

S.

6

There is a FPATH variable that should be set to point to the directory where the functions are defined. Check this link out - fpath

7

I'm not 100% sure i get this, is this saying create a libary of functions in another directory then ref this directory using the FPATH and just make calls to the required functions?

So if i have a file functions.sh that contains:

editSQLReleaseFile()
{
clear
echo "Editing..."
sleep 112
}

Then another file (say test.sh) with FPATH set to the location of the functions.sh file i can then make a call to editSQLReleaseFile from within test.sh?

i.e. in test.sh

echo "calling editSQLReleaseFile"
editSQLReleaseFile

?

8

It possible. What you have to do is to set the fpath, call autoload in the calling script and use the function. Like,

#!/bin/ksh
export FPATH=/dir/where/functions/are/in/scripts/ #better set this var in .profile
autoload #alias for typeset -fu; It loads the functions into memory
func1 #use the functions in the script.

I am not near a system, so have not tested it. But this is possible. Guys, please correct if wrong.

9

Is it possible to just make a direct call to a function in another script without having to do this FPATH stuff? I may wish to reuse some scripts that have already been written.

10

Put your functions in a file, and source that file in any script that needs those functions:

## Functions file: $HOME/bin/funcs
xx()
{
  printf "%s\n" "$@"
}

xy()
{
  shift
  printf "%s\n" "$@"  
}

## Script that uses functions

. "$HOME/bin/funcs"

xx 12 34 56
xy qw er ty
11

FPATH is not standard (ksh only).

12

That is not exactly correct. The way this works changes depending on whether you are using ksh88 or ksh93. Suppose I write a script that contains a command like this:
xyzzy arg1 arg2 arg3
That "xyzzy" might be a command or it might be a function. So ksh88 will scan PATH looking for "xyzzy". If it finds it on PATH, it must be a command. If it is not found, then FPATH is scanned, if it is found there, it must be a function. Suppose I have both a command called "xyzzy" and a function called "xyzzy". I'm stuck...it will find the command first. This is where autoloading comes in. By autoloading "xyzzy", I declare that it must be a function.

With ksh93, autoloading is supported but deprecated. Instead you can put a directory both in FPATH and PATH. Such a directory is assumed to contain functions only. But you can sequence the search of commands and functions by the order of the directories in PATH.

This is weird enough that I suggest you forget about FPATH and just use cfajohnson's suggestion.

13

Nice thing to learn. Else I would have been stuck to the same old thought process!!! Thanks for the explanation.