cheatsheets/makefile.md

Safe assignment

prefix ?= /usr/local

Cool stuff

	gitdir ?= $(shell git --exec-path)
	gitver ?= $(word 3,$(shell git --version))

Substitutions

	$(SOURCE:.cpp=.o)
	$(patsubst %.cpp, %.c, $(SOURCES))

Building files

	%.o: %.c
		ffmpeg -i $< > $@   # Input and output
		foo $^

Default task

	default:
		@echo "hello."
		@false