The programs getman and hexify are used to extract a plain ASCII man
page from a C program, encode it, then put it back into that same C
program (via "#include") along with some code to print out the encoded
version as ASCII.

Rather than explain all the bits and pieces and how to use these two
programs, I suggest you read Makefile and mkstemp.c in ../mkstemp; from
there it should be obvious how everything works.
