Add CLONE_PIDFD from Linux 5.2 to bits/sched.h

[Joseph Myers]

This patch adds the CLONE_PIDFD constant from Linux 5.2 to glibc's
bits/sched.h.

Tested for x86_64.

2019-08-05  Joseph Myers  <joseph@codesourcery.com>

	* sysdeps/unix/sysv/linux/bits/sched.h [__USE_GNU] (CLONE_PIDFD):
	New macro.

diff --git a/sysdeps/unix/sysv/linux/bits/sched.h b/sysdeps/unix/sysv/linux/bits/sched.h
index 828b878696..b67820cb49 100644
--- a/sysdeps/unix/sysv/linux/bits/sched.h
+++ b/sysdeps/unix/sysv/linux/bits/sched.h
@@ -44,6 +44,8 @@
 # define CLONE_FS      0x00000200 /* Set if fs info shared between processes.  */
 # define CLONE_FILES   0x00000400 /* Set if open files shared between processes.  */
 # define CLONE_SIGHAND 0x00000800 /* Set if signal handlers shared.  */
+# define CLONE_PIDFD   0x00001000 /* Set if a pidfd should be placed
+				     in parent.  */
 # define CLONE_PTRACE  0x00002000 /* Set if tracing continues on the child.  */
 # define CLONE_VFORK   0x00004000 /* Set if the parent wants the child to
 				     wake it up on mm_release.  */

-- 
Joseph S. Myers
joseph@codesourcery.com