similar to the atexit handlers. Idea and help deraadt@, ok deraadt@

malloc.c gets the first mmap() call (since it depends on that, for its
sbrk(0) use). ok deraadt@

first.

help get this right.

function pointers from the outside will segfault. Idea, hints and feedback
from deraadt. ok deraadt.

Noticed by deraadt@

aliases to fake up strtou?q().  espie@ OK.

that the first char in the line is not NUL after killing comments.

field separators as empty field.  This is not what we want for
whitespace-delimited fields.

o make first arg const since we don't modify it
o use strsep() instead of strtok() as strtok() changes internal state
o add some bounds checking and use strlcat() instead of pointer arithmetic
o ANSI function headers
Originally based on a patch from Lars J. Buitinck but much modified.

some brave soul should look at it.

XXX libraries should not use atexit(3) from within, as program can terminate
with _exit.

Also fix a typo; adapted from a patch by Moritz Jodeit

o) always close .Bl tags;
o) fix usage of .Xr;
millert@ ok

o) remove extra space in the end of line;
o) remove extra blank lines in the end of file;
o) remove .Pp before .Ss;
o) CAVEAT -> CAVEATS;
o) fix usage of .Fa;
o) <blank-line> -> .Pp;
o) wrap long lines;
millert@ ok

millert@ ok
deraadt@ ok to commit

will be overwritten by subsequent calls; suggested by pjanzen, ok millert

of getopt() to char variables instead of int lose on arches where char is
unsigned by default.
Clean the example by not pasting parts of <unistd.h> into it, and by not
using atoi(3).

millert@ ok