Fix errno handling in posix_openpt.

The implementation of posix_openpt on Linux can fail in a few extra
ways if the appropriate pseudo filesystems are not mounted etc.  In
some of these cases we have to explicitly set errno.

2 files changed, 10 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 99088df6ad..c46e962933 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2009-10-27  Andreas Schwab  <schwab@redhat.com>
+
+	* sysdeps/unix/sysv/linux/getpt.c (__posix_openpt): Make sure
+	errno is always set when returning unsuccessfully.
+
 2009-10-29  Andreas Schwab  <schwab@redhat.com>
 
 	* malloc/memusage.c (update_data): Fix index wraparound handling
diff --git a/sysdeps/unix/sysv/linux/getpt.c b/sysdeps/unix/sysv/linux/getpt.c
index bb1ea47643..6b26fdfcdc 100644
--- a/sysdeps/unix/sysv/linux/getpt.c
+++ b/sysdeps/unix/sysv/linux/getpt.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1998, 1999, 2001 Free Software Foundation, Inc.
+/* Copyright (C) 1998, 1999, 2001, 2009 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1998.
 
@@ -64,9 +64,10 @@ __posix_openpt (oflag)
 	    }
 
 	  /* If /dev/pts is not mounted then the UNIX98 pseudo terminals
-             are not usable.  */
+	     are not usable.  */
 	  __close (fd);
 	  have_no_dev_ptmx = 1;
+	  __set_errno (ENOENT);
 	}
       else
 	{
@@ -76,6 +77,8 @@ __posix_openpt (oflag)
 	    return -1;
 	}
     }
+  else
+    __set_errno (ENOENT);
 
   return -1;
 }