* pinfo.cc (EnumProcessesNT): Avoid 0 pids.

(EnumProcesses9x): Ditto.
* sigproc.cc (remove_childe): Eliminate.
(proc_subproc): Move remove_child stuff here.
(wait_subproc): Synchronize with proc_subproc when error occurs.  Add more
debugging info.
* sigproc.h (procstuff): Add an entry.
* spawn.cc (spawn_guts): Add sigframe here.

winsup/cygwin/sigproc.h

@@ -20,7 +20,8 @@ enum procstuff
   PROC_CHILDSTOPPED	= 2,	// a child stopped
   PROC_CHILDTERMINATED	= 3,	// a child died
   PROC_CLEARWAIT	= 4,	// clear all waits - signal arrived
-  PROC_WAIT		= 5	// setup for wait() for subproc
+  PROC_WAIT		= 5,	// setup for wait() for subproc
+  PROC_NOTHING		= 6	// nothing, really
 };
 
 typedef struct struct_waitq