This is a self-contained tutorial on using the make utility in Unix.
It is a set of directories designed to teach you how to write and use makefiles.
The directories are named lesson1, lesson2, ..., lesson10.
Each directory has a makefile in it.
You should start with the makefile in directory lesson1, and
proceed in numerically increasing order through the directories.
If you skip one, you will most likely not understand the rest,
because each builds on the lessons from the preceding directories.
Note: To use this tutorial, you should first go to the repository on GitHub
that contains it, either by clicking on the "View on GitHub" button,
or by manually loading the page
https://github.com/stewartweiss/Make-Tutorial.
Once you have that page open in your browser, you should download the
repository as a zipfile and extract it into a
directory on your Unix/Linux system. The rest of the instructions below
assume you have done this.
To download the repository as a zipfile, click the "Clone or download"
button, and then click the "Download ZIP" link and
follow the remaining instructions.
The lessons do not cover all you need to know about makefiles. They are designed to give you the basics, and perhaps a bit more. Once you master these, you should read the Make Manual.
These makefiles are based on the GNU make command. GNU's version of make is not the same as other versions of make found in UNIX systems, but it is POSIX-compliant. It has features not present in others, and it lacks some features that are present in others. But since it is POSIX-compliant and it is the most common version of make found on Linux systems, I chose to use it for teaching about make.
Each makefile has a lesson embedded in its comments. A comment in make starts with the pound sign "#" and ends with a newline character.
These lessons do not discuss how to name makefiles. I will briefly go over
that here. Makefiles are traditionally named either "makefile" or "Makefile".
The make command will look for a file with either name in the current working
directory. The GNU version of make tries the following names, in order:
GNUmakefile
makefile
Makefile
You should not name your makefile GNUmakefile; it is misleading and not portable.
I prefer the uppercase version, i.e., Makefile, since all of my source
files are always lowercase names and the other informational files,
such as this README, are uppercase.
On many systems, the default collating sequence used by the ls command
is to display uppercase before lowercase, so the makefile name will be
near the beginning of the directory listing.
To run the make command, make sure your working directory has a makefile
in it. If it is not one of the standard names described above you can use the
-f option to the make command. If the makefile is named MAKEFILE, you would type
make -f MAKEFILE
to use that file instead. If you do not want make to do anything but
just want to see what make might do, use the -n option, which does
not execute any commands but just displays which ones it would do:
make -n
There are many other things to know about running make, but these two options
are useful to remember as you progress through the lessons.
Lastly, the makefile in this top-level directory is the LAST part of this tutorial. You will not understand it until you have finished the tutorial. Save it for last.
Stewart Weiss Sept. 5, 2023