These episodes introduce a build tool called Make; a parallel lecture introduces an alternative build tool called SCons.

Requires: The Unix Shell

Introduces: Make, a tool for automating processes

Motivating questions:

1. I have to rebuild the figures for my paper every time the data is updated. Is there a way to automate this?
2. My program consists of 10 files of FORTRAN with several interdependencies. How can I automatically rebuild the files that are affected by a change?

Lectures:

1. Introduction (pdf, ppt)
   • Any task that is worth repeating is worth automating
   • Most tasks come with a set of dependencies that have to be fulfilled first.
   • Make is a widely used tool for automating tasks that involve dependencies.
2. Basics (pdf, ppt)
   • Makefiles list prerequisites for a task and the set of commands to recreate that task.
   • Make automatically reruns a task if any of its prerequisites are more up to date that the current output.
3. Patterns (pdf, ppt)
   • Makefiles can include patterns to eliminate redundant typing.
   • Make also accepts wildcard patterns like * to help represent long lists of files.
4. Rules (pdf, ppt)
   • Sometimes redundant Makefile statements can be combined using pattern rules.
   • Be careful, however, that the original tree of dependencies is preserved and that rules containing a wildcard aren’t intended to match files that are created by the Makefile itself.
5. Macros (pdf, ppt)
   • Like any other programming language, Make allows the introduction of variables.
   • Variables are declared using a = and accessed by typing ${VARIABLE}
   • Make also allows the declaration of config files that help define variables when the program needs to run on machines with different operating systems.