* sigproc.cc (proc_info): Rename proc_exists which takes a pid to "pid_exists".

* shared.h: Split out "child_info" stuff into a new header file and use where
necessary.  Declare pid_exists.
* child_info.h: New file.

winsup/cygwin/child_info.h

@@ -0,0 +1,63 @@
+/* childinfo.h: shared child info for cygwin
+
+   Copyright 2000 Red Hat, Inc.
+
+This file is part of Cygwin.
+
+This software is a copyrighted work licensed under the terms of the
+Cygwin license.  Please consult the file "CYGWIN_LICENSE" for
+details. */
+
+enum
+{
+  PROC_MAGIC = 0xaf08f000,
+  PROC_FORK = PROC_MAGIC + 1,
+  PROC_EXEC = PROC_MAGIC + 2,
+  PROC_SPAWN = PROC_MAGIC + 3,
+  PROC_FORK1 = PROC_MAGIC + 4	// Newer versions provide stack
+				// location information
+};
+
+#define PROC_MAGIC_MASK 0xff00f000
+#define PROC_MAGIC_GENERIC 0xaf00f000
+#define PROC_MAGIC_VER_MASK 0x0ff0000
+
+#define EXEC_MAGIC_SIZE sizeof(child_info)
+class child_info
+{
+public:
+  DWORD zero[1];	// must be zeroed
+  DWORD cb;		// size of this record
+  DWORD type;		// type of record
+  int cygpid;		// cygwin pid of child process
+  HANDLE subproc_ready;	// used for synchronization with parent
+  HANDLE shared_h;
+  HANDLE console_h;
+  HANDLE parent_alive;	// handle of thread used to track children
+  HANDLE myself_pinfo;
+  ~child_info ()
+  {
+    if (myself_pinfo)
+      CloseHandle (myself_pinfo);
+  }
+};
+
+class child_info_fork: public child_info
+{
+public:
+  HANDLE forker_finished;// for synchronization with child
+  DWORD stacksize;	// size of parent stack
+  void *heaptop;
+  void *heapbase;
+  void *heapptr;
+  jmp_buf jmp;		// where child will jump to
+  void *stacktop;	// location of top of parent stack
+  void *stackbottom;	// location of bottom of parent stack
+};
+
+void __stdcall init_child_info (DWORD, child_info *, int, HANDLE);
+
+extern child_info_fork *child_proc_info;
+
+/* non-NULL if this process is a child of a cygwin process */
+extern HANDLE parent_alive;