File and directory check in Makefile
I needed to do some conditional target-based execution via my makefiles. To make them truly generic, I needed to deduce directory structure that I was sitting in.
One of the things I had to do was to check for existence of a file or directory. Now since Makefiles have a different syntax than ordinary shell, compounded by the problem of interfacing with the *nix shell, it took me some time to figure out/learn how to do this.
The syntax (for GNU make) is
At first I tried to do
but this did'nt work, because the shell interface does not return a numeric status (atleast I think so). But in the syntax that works, by the power of logic, the "echo exists" will take place if and only if the "shell" command works.
Ergo, I can check for directories.
whew!!
One of the things I had to do was to check for existence of a file or directory. Now since Makefiles have a different syntax than ordinary shell, compounded by the problem of interfacing with the *nix shell, it took me some time to figure out/learn how to do this.
The syntax (for GNU make) is
ifeq (exists, $(shell [ -d directory_name ] ) && echo exists )
$(warning hi... I did it)
endif
At first I tried to do
ifeq (1, $(shell [ -d directory_name ] ) )
$(warning hi... I did it)
endif
but this did'nt work, because the shell interface does not return a numeric status (atleast I think so). But in the syntax that works, by the power of logic, the "echo exists" will take place if and only if the "shell" command works.
Ergo, I can check for directories.
whew!!
del.icio.us Tags: software
This entry was posted
on 8/24/2005 at 8/24/2005 09:53:00 PM.
