add some introductory comments to the clntsrv example

src/l4/pkg/examples/clntsrv/Makefile

@@ -1,7 +1,11 @@
+# Relative path to the directory of this packages (i.e., the clntsrv package).
 PKGDIR          ?= .
+# Relative path back to the src/l4 directory.
 L4DIR           ?= $(PKGDIR)/../../..
 
+# List of all subdirectories that the build system should look at.
 TARGET = src configs
 
+# The included make script reads the variables defined above to recurse into the subdirectories.
 include $(L4DIR)/mk/subdir.mk
 

src/l4/pkg/examples/clntsrv/configs/Makefile

@@ -1,8 +1,11 @@
 PKGDIR          ?= ../..
 L4DIR           ?= $(PKGDIR)/../..
 
+# Specify the subdirectory to put the following assets into.
 PKGNAME = ex_clntsrv
+# Specify our Ned scripts.
 SRC_ASSETS_NED = clntsrv.cfg
+# Specify our module list.
 SRC_ASSETS_MODLIST = modules.list
 
 include $(L4DIR)/mk/assets.mk

src/l4/pkg/examples/clntsrv/src/Makefile

@@ -1,9 +1,13 @@
 PKGDIR          ?= ..
 L4DIR           ?= $(PKGDIR)/../../..
 
+# List of binaries that are generated by this Makefile.
 TARGET                   = ex_clntsrv-server ex_clntsrv-client
+# The list of source files for each binary.
 SRC_CC_ex_clntsrv-server = server.cc
 SRC_CC_ex_clntsrv-client = client.cc
+# This is our memory-allocator library we will develop during a later assignment.
+# You also need to link to libstdc++ to be able to use some C++ features in the allocator later on.
 REQUIRES_LIBS            = libc_be_mem libstdc++
 
 include $(L4DIR)/mk/prog.mk