I like to use make and makefiles on my projects and today I needed to call a makefile from within another makefile... I was pretty sure there was a “proper” way to do it, so I went ahead and looked it up.
A quick search revealed I should use $(MAKE) instead of typing make and that I could also use the option -C to change the directory from where I'm reading my makefile.
As a simple example, consider the following directory structure:
- root
|- Makefile
|- subfolder
|- MakefilePaste the following in root/Makefile:
root:
@echo "Root directory makefile."
nest:
@echo "About to call nested makefile."
$(MAKE) -C subfolder $@Running make root from within the folder root should print “Root directory makefile.”.
Now, paste the following in root/subfolder/Makefile:
nest:
@echo "From nested Makefile"
up:
@echo "About to call root makefile"
$(MAKE) -C .. rootIf you're in root, running make nest should print
About to call nested makefile.
/path/to/make -C subfolder nest
From nested MakefileIf you're in subfolder, running make up should print
About to call root makefile
path/to/make -C .. root
Root directory makefile.Also note that in the top rule nest I used $@ to refer to a rule with the same name in subfolder/Makefile, whereas in the rule up I used the explicit target root.
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