---
title:
- Making Makefiles
author:
- Malin

theme:
- Warsaw
colortheme:
- orchid
---

# Intro

- input, process, output.
- automatic idempotence
- *Gotcha*: directories
- This, that, and these

***

# Variables

- From your shell.
- New variables.
- Filenames as variables.
- *Gotcha*: no shell variables, only make!

## Equality

- Variables with '=', never ':='.
- *Gotcha*: one shell per line.
- Variables as shell output.


***


# Phonies, and the Problems with Lies

- clean (common)
- check (excellent)

***


## Non-Compiling Checks

- `make` -n
- *Gotcha*: shell output variables.

***


# The Fourth Sigil: `%`

- Standard rules, e.g. ImageMagick, copying, et c.
- *Gotcha*: intermediaries are deleted.

***


# Bling: make2graph

- *Gotcha*: completely outdated.

***

# Inclusivity

- `include dir/Makefile`
- *Gotcha*: directory has not changed
- `$(MAKEFILE_LIST)`


# Special Commands

- dirname
- `DIR = test -d $(dirname $@) || mkdir $(dirname $@)`
- patsubst
- Wildcards (or not?)

# Maintanance

- backups
- saving files