Passing variables from shell scripts to GNU Make

How to pass variables from shell scripts to GNU make

Make is a really useful tool when you want to be able to write simple jobs. You don’t just need to use it for compiling source code. One thing you may wish to do is be able to pass variables to make commands. Lets take a look at a pretty simple Makefile that will delete all the indexes in Elastic Search.

endpoint := localhost:9200
all:
        curl -XDELETE ${endpoint}/_all

Running ‘make’ will spawn curl and delete the localhost:9200/_all

If we want to override the variable $endpoint with say ‘es.remote.dodwell.us:9200’ we can do that with the following:

[email protected]:~/Makefiles$ make endpoint="es.remote.dodwell.us:9200"