multiple optional add-on sis files

[proberts]

We have an application that will have many (100+) optional add-on packages (all passive content). Any combination of add-ons can be installed/uninstalled and each can be upgraded.

I'm currently installing each as TYPE=SA with a dependency for the main application. This requires that the user know and/or remember where they installed the original app and then install the add-on to the same memory location. I'd like to make drive selection automatic, but can't find a way to do it. Any suggestions? (What I'd really like to do is programmatically set the value of ! in the PKG file.)

Here's what I've tried and how it's failed:

- - -

TYPE=SP

>>>Changes main app version number causing problem with subsequent add-ons installs and removals

- - -

IF exists("c:\system\apps\myapp")
...install to c:
ELSEIF exists("e:...")
...install to e:
ELSE
...show error and exit
ENDIF

>>>SIS ends up with two copies of all files. Neither TEXTEXIT nor TEXTABORT force the install to cancel.

- - -

IF exists("!:\system\apps\myapp")
...install to !:
ELSE
...show error and exit
ENDIF

>>> exists("!:\...") always evals as false. Same problem with TEXTEXIT and TEXTABORT

- - -

TEXTFILE: tell user to install to same dir
install to !:\

>>> TEXTFILE displayed after install device dialog

- - -

[wizard_hu_]

Have you checked for path or file? According to the documentation "exists" works with filenames.

[proberts]

Have you checked for path or file? According to the documentation "exists" works with filenames.

I have...It does work with explicit paths, like "c:\path\to\file" or "e:\path\to\dir", but then I have two copies of the file I want to install in the SIS (see pseudo-code in OP). If I try it with the bang variable, "!:\path\to\file", exists always evaluates false.