Build the POSIX binding using mmc --make.

Building the POSIX binding using mmc --make by default and just have mmake
forward its work to that.  Using mmc --make means things like library grade
exclusions will work properly.

Exclude non-C grades from the grade set in which to install the POSIX binding.

Shift a POSIX binding sample into the samples subdirectory.

extras/posix/Makefile:
extras/posix/Mercury.options:
    Build the POSIX binding using mmc --make.

extras/posix/Mmakefile:
    Redirect mmake to use the normal Makefile.

extras/posix/hello.m:
    Shift this file into the samples subdirectory.

extras/samples/Makefile:
    Set up things to build the samples against a libposix in the
    parent directory.

extras/samples/Mmakefile:
    Delete this file.

extras/posix/Makefile

@@ -0,0 +1,29 @@
+#-----------------------------------------------------------------------------#
+# vim: ts=8 sw=8 noexpandtab
+#-----------------------------------------------------------------------------#
+# Copyright (C) 2011 The University of Melbourne.
+# Copyright (C) 2015, 2018-2019 The Mercury team.
+# This file is distributed under the terms specified in COPYING.LIB.
+#-----------------------------------------------------------------------------#
+
+# Build the posix library using mmc --make.
+
+TARGET = posix
+MMC = mmc
+
+.PHONY: build
+build: posix_workarounds.o
+	$(MMC) --make lib$(TARGET)
+
+.PHONY: install
+install: posix_workarounds.o
+	$(MMC) --make lib$(TARGET).install
+
+posix_workarounds.o: posix_workarounds.c
+
+.PHONY: realclean
+realclean:
+	cd samples && $(MAKE) realclean
+	$(MMC) --make $(TARGET).realclean
+	/bin/rm -f posix_workarounds.o
+	/bin/rm -rf Mercury

extras/posix/Mercury.options

@@ -0,0 +1,6 @@
+MCFLAGS = \
+	--libgrades-exclude java \
+	--libgrades-exclude csharp \
+	--libgrades-exclude erlang \
+	--link-object posix_workarounds.o \
+	--extra-library-header posix_workarounds.h

extras/posix/Mmakefile

@@ -6,42 +6,27 @@
 # This file is distributed under the terms specified in COPYING.LIB.
 #-----------------------------------------------------------------------------#
 
-INSTALL_PREFIX := $(INSTALL_PREFIX)/extras
+# This is file exists so that do an `mmake' from the top-level of the extras
+# distribution works.  The actual work of building this library is done
+# using the Makefile and mmc --make.  This file just forwards all the work
+# to there.
 
--include ../Mmake.params
+MAIN_TARGET=build
 
-# The following is needed (on some systems) to enable declarations of
-# Posix functions in standard C header files.
-MGNUCFLAGS = --no-ansi
-
-# This library has some parts that are implemented in C
-# rather than in Mercury.  The following lines ensure that
-# the .h and .o files for those parts get included in the library.
-ADDITIONAL_HDRS = posix_workarounds.h
-MLOBJS = posix_workarounds.$O
-MLPICOBJS = posix_workarounds.$(EXT_FOR_PIC_OBJECTS)
-
-.PHONY: default_target
-default_target: all
+.PHONY: build
+build:
+	$(MAKE) build
 
+# The depend target does nothing, mmc --make will handle dependencies
+# automatically.
+#
 .PHONY: depend
-depend: posix.depend hello.depend
-
-.PHONY: all
-all: libposix hello
-
-.PHONY: check
-check: hello
-	./hello
+depend:
 
 .PHONY: install
-install: libposix.install
-	cp $(ADDITIONAL_HDRS) $(INSTALL_PREFIX)/lib/mercury/inc
-
-.PHONY: clean
-clean:
-	-/bin/rm -f posix_workarounds.$(O)
-	-/bin/rm -f posix_workarounds.$(EXT_FOR_PIC_OBJECTS)
+install:
+	$(MAKE) install INSTALL_PREFIX=$(INSTALL_PREFIX)/extras
 
 .PHONY: realclean
-realclean: clean
+realclean:
+	$(MAKE) realclean

extras/posix/samples/Makefile

@@ -0,0 +1,16 @@
+DEMOS = mdprof_cgid hello
+MMC = mmc
+
+# The following target builds the demos and links them against the posix
+# library in the parent directory in situ.
+#
+all:
+	$(MMC) --search-lib-files-dir .. \
+		--init-file ../posix.init \
+		--link-object ../libposix.a \
+		--make $(DEMOS)
+
+.PHONY: realclean
+realclean:
+	$(MMC) --make $(DEMOS:%=%.realclean)
+	/bin/rm -rf Mercury