You need:

-a C compiler (gcc)
-flex/lex or a similar behaving lexical analyzer
(only if you choose to regenerate lex.yy.c; to do so type make mrproper)
-make

Then do:

#> make

Copy "genproto" to a place where it suits you.


Flex/lex:
---------

If you choose to regenerate the lex.yy.c via flex you can choose different 
code size/speed-tradeoffs via specifying LEXFLAGS in the Makefile.

slowest & smallest
	-Cem
	-Cm
	-Ce
	-C
	-C{f,F}e
	-C{f,F}
	-C{f,F}a
fastest & largest

See the man-page for more detail.