Reno /usr/include/signal.h bad for ANSI compilers

[Jonathan Stone]

Symptom::
   Builds of the X window system fail on 4.3-Reno when using gcc,
   with many error messages about a parse error in line 209 of
   /usr/include/signal.h.

Bug::
    /usr/include/signal.h references the type pid_t when __STDC__ is
    defined, but does not define this type anywhere, or #include a
    definition of it.

Fix::
   Make /usr/include/signal.h (really /sys/sys/signal.h) include
   the definition of pid_t from <sys/types.h> when  __STDC__ is
   defined (and perhaps when it's not, depending on taste).
   The following patch does this, albeit in questionable style.

   This may or may not be appropriate when compiling the kernel.

Subject: Reno /usr/include/signal.h bad for ANSI compilers
*** /usr/src/sys/sys/signal.h.dist	Sun Jul 29 06:55:41 1990
--- /usr/src/sys/sys/signal.h	Thu May  9 15:58:04 1991
***************
*** 206,211 ****
--- 206,212 ----
  #endif /* KERNEL */
  
  #if __STDC__ || c_plusplus
+ #include <sys/types.h>
  int kill(pid_t, int);
  int sigaction(int, const struct sigaction *, struct sigaction *);
  int sigprocmask(int, const sigset_t *, sigset_t *);