Use mkstemps() instead of mkstemp() in sudoedit. This allows sudoedit

to preserve the file extension (if any) which may be used by the editor
(like emacs) to choose the editing mode.

include/missing.h

@@ -63,8 +63,8 @@ size_t strlcpy(char *, const char *, size_t);
 #ifndef HAVE_MEMRCHR
 void *memrchr(const void *, int, size_t);
 #endif
-#ifndef HAVE_MKSTEMP
-int mkstemp(char *);
+#ifndef HAVE_MKSTEMPS
+int mkstemps(char *);
 #endif
 #ifndef HAVE_NANOSLEEP
 int nanosleep(const struct timespec *, struct timespec *);