Re: Executing Commands for Items in a List?

[Jonah Bishop]

On Tue, Feb 9, 2010 at 4:45 PM, Paul Smith <address@hidden> wrote:

On Tue, 2010-02-09 at 16:32 -0500, Jonah Bishop wrote:
> I'd like to do what I think should be very simple, but I can't find
> any examples of what I'm trying to do. I have a variable in a make
> file that has a bunch of directory names in it, and I'd like to
> perform multiple actions on those directory names, namely by "looping"
> over the list. The "foreach" construct was what I went to initially,
> and might be the right goods, but I can't figure out the right syntax.

> DIRS = alpha bravo charlie delta foxtrot
>
> All I want to do is "loop" over that list, performing some shell
> operations (or issuing other commands) on those directories. Is there
> a simple way to do that?

The simplest way is to use shell constructs:

       dostuff:
               for dir in $(DIRS); do \
                       stuff-1 $$dir ; \
                       stuff-2 $$dir ; \
               done

There are a lot of sub-optimal things about this, such as no parallel
capability, no error handling, etc. but without more details about what
you really want to do that's the simplest solution that will solve your
problem.

Here's some more information that may be helpful. I have a bunch of child directories that each have their own makefiles. I want to iterate over a list of those directories, changing into each, and issuing the appropriate make call in each. Similarly, I'd like to have a "make clean" target to do the same thing: loop over the directories and do the appropriate "make clean" call.

Hopefully that makes things a little clearer.