replace 3 files and add 1 prototype

Changes to be committed:
	modified:   include/extern.h
	modified:   src/apply.c
	modified:   src/sys.c
	modified:   win/tty/wintty.c

The 3 files appeared to be missing sections. The erronoeous
versions have been emailed to the win32 team to determine
their fate.

Adds a missing prototype also.

include/extern.h

@@ -742,6 +742,7 @@ E boolean NDECL(recover_savefile);
 #ifdef SYSCF_FILE
 E void NDECL(assure_syscf_file);
 #endif
+E int FDECL(nhclose, (int));
 #ifdef HOLD_LOCKFILE_OPEN
 E void NDECL(really_close);
 #endif