CVS: Gnu make

[Li, Jerry]

Hi, All:

I know this question has nothing to do with CVS, however, I am thinking
somebody in this group should be an expert on Make file.

I am using GnuMake 3.79.1, and write makefiles which will work on both
Windows NT and UNIX. Below is my sample makefile.

****************************************************************************
****************
OS := WINDOWS_NT

#FOR UNIX
#OS := UNIX

if "$(OS)" "WINDOWS_NT"
PATH_SEP := \                   # this is where I am having with, PATH_SEP
gets nothing on NT
DEL := erase /q/f/s
endif

if "$(OS)" "UNIX"
PATH_SEP := /
DEL := rm -rf
endif

CLASS_DIR := $(WORK_DIR)$(PATH_SEP)classes  # where WORK_DIR is a system
environment variable

clean:
        @$(DEL) $(CLASS_DIR)


****************************************************************************
**************

The above Makefile will not work on Windows NT because Gnu Make treats \ as
a line continuator, therefore, my question is how to protect \ in Gnu Make.

thanks a lot for your help in advance.

Jerry