if-statementmakefiledirectorygnu-makegetdirectories

How to count directories in make file

I have makefile(.mke) on Windows and I need to count directories in a folder which start with "Install" and then make if clause to throw an exception if there are more than one directory like this.

For example: 

Files: Install.1.0, Install.2.0, Install.3.0..

I have $(SrcRoot) variable and I need to count directories in this folder then make if clause that "if (numberOfDirs > 1) throw an error."

In my example there would be an exception because there are 3 Install.. folders.

Solution

  • If by "throw an exception" you mean abort Make with an error message, this will do it:

    INSTALLS := $(wildcard $(SrcRoot)/Install*)

ifneq (,$(word 2,$(INSTALLS)))
$(error there are too many Install directories)
endif