K 10
svn:author
V 6
iulius
K 8
svn:date
V 27
2014-12-07T18:33:37.483968Z
K 7
svn:log
V 480
Remove super-ancient definitions of ptrdiff_t, atexit and strtoul

These functions were missing on some pre-C89 systems like SunOS.
(The on_exit stuff may be for ULTRIX.)  They're present on all modern
systems and can just be used unconditionally.

Also, string.h is now universal.  One has to go back to SunOS to find
a version of UNIX that doesn't have it, and it's standardized by ISO C.
It can be included unconditionally.

Remove checking for stddef.h, not used in the code.

END
