Var assignment
uglify = $(uglify) # assignment
compressor := $(uglify) # lazy assignment
prefix ?= /usr/local # safe assignment
Magic variables
out.o: src.c src.h
$@ # "out.o" (target)
$< # "src.c" (first prerequisite)
$^ # "src.c src.h" (all prerequisites)
%.o: %.c
$% # target member name ("foo" in "foo.c")
also:
$+ # prerequisites (all, with duplication)
$? # prerequisites (new ones)
$| # prerequisites (order-only?)
$* # basename without extension of the target (?)
$(@D) # target directory
Command prefixes
Prefix |
Description |
- |
Ignore errors |
@ |
Don’t print command |
+ |
Run even if Make is in ‘don’t execute’ mode |
build:
@echo "compiling"
-gcc $< $@
-include .depend
Find files
js_files := $(wildcard test/*.js)
all_files := $(shell find images -name "*")
Substitutions
file = $(SOURCE:.cpp=.o) # foo.cpp => foo.o
outputs = $(files:src/%.coffee=lib/%.js)
outputs = $(patsubst %.c, %.o, $(wildcard *.c))
assets = $(patsubst images/%, assets/%, $(wildcard images/*))
More functions
$(strip $(string_var))
$(filter %.less, $(files))
$(filter-out %.less, $(files))
Building files
%.o: %.c
ffmpeg -i $< > $@ # Input and output
foo $^
Includes
-include foo.make
Options
make
-e, --environment-overrides
-B, --always-make
-s, --silent
-j, --jobs=N # parallel processing
Conditionals
foo: $(objects)
ifeq ($(CC),gcc)
$(CC) -o foo $(objects) $(libs_for_gcc)
else
$(CC) -o foo $(objects) $(normal_libs)
endif
Recursive
deploy:
$(MAKE) deploy2
Further reading