Break task into steps.
Write code to represent each step.

Your question is incredibly generic. In the case of installing software on a bunch of computers, what is often done is to create a complete binary image of a fully confugured machine and copy that image onto all the other machines. It then becomes quite obvious how you might write such a tool, and make it operate over networks, etc. There are several sysadmin tools that do this sort of thing.

In short, the solution depends on the problem and its domain.

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Thanks to Kylotan for the idea!

Find the common level of abstraction. Manipulating files (in a detailed fashion) is very platform-specific, so it''s not easy to write a "multi-OS" wizard. Say you wished to write it for different versions of Windows, the next question is which tool has the lowest cost in terms of time for identical yield. Scratch C and its derivatives; go with VB. On UNIX platforms, use Bourne shell (/bin/sh) scripts, because every UNIX platform is virtually guaranteed to have it installed.

The actual task list then looks like this:
1. Verify system meets minimum requirements.
2. Verify disk space.
3. Copy files.
4. Miscellaneous configuration.

The last step often includes fiddling with the registry on Windows machines, but that''s not a difficult task.

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Thanks to Kylotan for the idea!

quote:Original post by tom76
Well ok I''ll pick an example. What if you created a wizard to install some software onto a computer, and wanted to test this wizard on different operating systems or differently configured PCs.

Bigger companies that are doing a lot of testing purchase special products to do things like this. Programs like silktest http://www.segue.com/html/s_solutions/silk/s_family.htm are very useful for doing something like this.

People who have less cash to throw around just add command line interfaces to their installers (If you''re using an install technology like Wise or Installshield this is pretty trivial) Then you can write batch scripts that run the installer and check that all the files are were they should be.