Check that /dev/pts is mounted.

(_PATH_DEVPTS, DEVPTS_SUPER_MAGIC): New definitions.
(_PATH_DEVPTMX): Use _PATH_DEV.

diff --git a/sysdeps/unix/sysv/linux/getpt.c b/sysdeps/unix/sysv/linux/getpt.c
index d2e0f1a7b8a83e8d89ea2fc2031d96e6f73b0fc6..511b9004c054546820323ffa78f32f1974db5220 100644 (file)
--- a/sysdeps/unix/sysv/linux/getpt.c
+++ b/sysdeps/unix/sysv/linux/getpt.c
@@ -20,9 +20,17 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <stdlib.h>
+#include <unistd.h>
+#include <paths.h>
+#include <sys/statfs.h>
+
+/* Constant that identifies the `devpts' filesystem.  */
+#define DEVPTS_SUPER_MAGIC     0x1cd1
 
 /* Path to the master pseudo terminal cloning device.  */
-#define _PATH_DEVPTMX "/dev/ptmx"
+#define _PATH_DEVPTMX _PATH_DEV "ptmx"
+/* Directory containing the UNIX98 pseudo terminals.  */
+#define _PATH_DEVPTS _PATH_DEV "pts"
 
 /* Prototype for function that opens BSD-style master pseudo-terminals.  */
 int __bsd_getpt (void);
@@ -38,7 +46,25 @@ __getpt (void)
     {
       fd = __open (_PATH_DEVPTMX, O_RDWR);
       if (fd != -1)
-       return fd;
+       {
+         struct statfs fsbuf;
+         static int devpts_mounted;
+
+         /* Check that the /dev/pts filesystem is mounted.  */
+         if (devpts_mounted
+             || (__statfs (_PATH_DEVPTS, &fsbuf) == 0
+                 && fsbuf.f_type == DEVPTS_SUPER_MAGIC))
+           {
+             /* Everything is ok.  */
+             devpts_mounted = 1;
+             return fd;
+           }
+
+         /* If /dev/pts is not mounted then the UNIX98 pseudo terminals
+             are not usable.  */
+         __close (fd);
+         have_no_dev_ptmx = 1;
+       }
       else
        {
          if (errno == ENOENT || errno == ENODEV)