The additional ':' after 'main.c' had no effect on the compilation since
the suffix is removed when computing the list of object files. The ':'
excluded main.c from the dependency computation and from lint.
By defining CPPFLAGS instead of CFLAGS, the default "-O2" steps in
again, and the proper flags are passed to lint, which did not work
before at all because it could not find an included file.
The second of the '$$?' was spelled only '$?'. At the time where this
shell expression was evaluated, it had already been overwritten by the
preceding command '['.
o close more leaking file descriptors for CGI and daemon mode
o add subdirs for build "debug" and "small" versions
o clean up a bad merge / duplicate code
o make mmap() usage portable, fixes linux & ranges: support
o document the -f option
o daemon mode now serves 6 files per child
