https://sourceware.org/ml/libc-alpha/2019-12/msg00799.html

to commit after 2.31 is released

diff --git a/sysdeps/unix/bsd/getpt.c b/sysdeps/unix/bsd/getpt.c
index 46207f4e62..0eff0b54a3 100644
--- a/sysdeps/unix/bsd/getpt.c
+++ b/sysdeps/unix/bsd/getpt.c
@@ -41,7 +41,7 @@ const char __libc_ptyname2[] attribute_hidden = PTYNAME2;
 
 /* Open a master pseudo terminal and return its file descriptor.  */
 int
-__getpt (void)
+__bsd_openpt (int oflag)
 {
   char buf[sizeof (_PATH_PTY) + 2];
   const char *p, *q;
@@ -61,7 +61,7 @@ __getpt (void)
 
 	  s[1] = *q;
 
-	  fd = __open (buf, O_RDWR);
+	  fd = __open (buf, oflag);
 	  if (fd != -1)
 	    return fd;
 
@@ -74,18 +74,20 @@ __getpt (void)
   return -1;
 }
 
-#undef __getpt
+#ifndef HAVE_GETPT
+int
+__getpt (void)
+{
+  return __bsd_openpt (O_RDWR);
+}
 weak_alias (__getpt, getpt)
+#endif
 
 #ifndef HAVE_POSIX_OPENPT
-/* We cannot define posix_openpt in general for BSD systems.  */
 int
 __posix_openpt (int oflag)
 {
-  __set_errno (ENOSYS);
-  return -1;
+  return __bsd_openpt (oflag);
 }
 weak_alias (__posix_openpt, posix_openpt)
-
-stub_warning (posix_openpt)
 #endif
diff --git a/sysdeps/unix/sysv/linux/getpt.c b/sysdeps/unix/sysv/linux/getpt.c
index cdde8377f5..1cb99d5185 100644
--- a/sysdeps/unix/sysv/linux/getpt.c
+++ b/sysdeps/unix/sysv/linux/getpt.c
@@ -31,7 +31,7 @@
 #define _PATH_DEVPTS _PATH_DEV "pts"
 
 /* Prototype for function that opens BSD-style master pseudo-terminals.  */
-extern int __bsd_getpt (void) attribute_hidden;
+extern int __bsd_openpt (int oflag) attribute_hidden;
 
 /* Open a master pseudo terminal and return its file descriptor.  */
 int
@@ -88,14 +88,15 @@ __getpt (void)
 {
   int fd = __posix_openpt (O_RDWR);
   if (fd == -1)
-    fd = __bsd_getpt ();
+    fd = __bsd_openpt (O_RDWR);
   return fd;
 }
+weak_alias (__getpt, getpt)
 
 
 #define PTYNAME1 "pqrstuvwxyzabcde";
 #define PTYNAME2 "0123456789abcdef";
 
-#define __getpt __bsd_getpt
+#define HAVE_GETPT
 #define HAVE_POSIX_OPENPT
 #include <sysdeps/unix/bsd/getpt.c>