diff --git a/ChangeLog b/ChangeLog
index 4ad93ce0e6..df482b947e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,4 +1,8 @@
-1998-11-05 1998  H.J. Lu  <hjl@gnu.org> 
+1998-10-28  H.J. Lu  <hjl@gnu.org> 
+ 
+	* posix/getopt.h: Add "__" to arguments in prototypes. 
+ 
+1998-11-05  H.J. Lu  <hjl@gnu.org> 
  
 	* libio/iofgets.c (_IO_fgets): Don't report error 
 	if something was read in and errno is set to 
@@ -11,7 +15,7 @@
 	header; it defines too much.  Provide a local definition of struct 
 	sockaddr_pkt and a comment advising against its use. 
  
-1998-11-06 1998  Andreas Schwab  <schwab@issan.cs.uni-dortmund.de> 
+1998-11-06  Andreas Schwab  <schwab@issan.cs.uni-dortmund.de> 
  
 	* extra-lib.mk: Avoid empty include list. 
  
diff --git a/posix/getopt.h b/posix/getopt.h
index ffb550b449..b0147e9d2a 100644
--- a/posix/getopt.h
+++ b/posix/getopt.h
@@ -131,23 +131,23 @@ struct option
 /* Many other libraries have conflicting prototypes for getopt, with
    differences in the consts, in stdlib.h.  To avoid compilation
    errors, only prototype getopt for the GNU C library.  */
-extern int getopt (int argc, char *const *argv, const char *shortopts);
+extern int getopt (int __argc, char *const *__argv, const char *__shortopts);
 # else /* not __GNU_LIBRARY__ */
 extern int getopt ();
 # endif /* __GNU_LIBRARY__ */
 
 # ifndef __need_getopt
-extern int getopt_long (int argc, char *const *argv, const char *shortopts,
-		        const struct option *longopts, int *longind);
-extern int getopt_long_only (int argc, char *const *argv,
-			     const char *shortopts,
-		             const struct option *longopts, int *longind);
+extern int getopt_long (int __argc, char *const *__argv, const char *__shortopts,
+		        const struct option *__longopts, int *__longind);
+extern int getopt_long_only (int __argc, char *const *__argv,
+			     const char *__shortopts,
+		             const struct option *__longopts, int *__longind);
 
 /* Internal only.  Users should not call this directly.  */
-extern int _getopt_internal (int argc, char *const *argv,
-			     const char *shortopts,
-		             const struct option *longopts, int *longind,
-			     int long_only);
+extern int _getopt_internal (int __argc, char *const *__argv,
+			     const char *__shortopts,
+		             const struct option *__longopts, int *__longind,
+			     int __long_only);
 # endif
 #else /* not __STDC__ */
 extern int getopt ();