Re: (should-be) simple directory parsing

[Paul D. Smith]

%% "galathaea galathaea" <address@hidden> writes:

  gg> Recursive variable `TEST10' references itself (eventually).

  gg> which, of course, was the point.  I found that my test code had
  gg> been using an experimental make version "3.81rc" which I had
  gg> installed on to my test machine from a different project.  The
  gg> version that fails (and that I need working code for) is 3.79.1.

The ability to use recursive functions with "call" was added in 3.80 I
believe.

  gg> I can do this in shell scripting really easily:

  gg> pwd | sed -e "s/\/TOP.*$//"

  gg> but when I try a naive translation to makefilese:

  gg> $(shell pwd | sed -e "s/\/TOP.*$//")

  gg> I get nothing.  I obviously do not understand how to get pipes
  gg> working in shell calls in makefiles, but I've tried a couple of
  gg> different ways using quotes and \" escaping the sed command
  gg> quotes, all without luck.

Your problem doesn't have anything to do with _SHELL_ quoting and
everything to do with _MAKE_ quoting.

As with any other string evaluated by make, any time you want a literal
dollar sign ($) to appear you have to escape it as two dollar signs
($$).  So you want:

    dir := $(shell pwd | sed -e "s,/TOP.*$$,,")

(note in sed you can use any character as a delimiter, not just "/";
handy if your pattern contains "/" chars).

  gg> I suspect this is the easiest task in the world and every makefile
  gg> in the world that I failed to look at today has it right there in
  gg> plain view.  I suspect there is a one-liner that does this in some
  gg> obvious way, and I am just wasting time with obscure back-routes.

I don't know about that, but if it were me I'd probably use something
like this:

    dir := $(word 1,$(subst /TOP, ,$(CURDIR)))

-- 
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