Make MSG_NOSIGNAL available to native programs.

Bump FreeBSD_version to note this change.

Reviewed by: sobomax

lib/libc/sys/send.2

@@ -103,11 +103,12 @@ The
 .Fa flags
 argument may include one or more of the following:
 .Bd -literal
-#define	MSG_OOB		0x1   /* process out-of-band data */
-#define	MSG_PEEK	0x2   /* peek at incoming message */
-#define	MSG_DONTROUTE	0x4   /* bypass routing, use direct interface */
-#define MSG_EOR		0x8   /* data completes record */
-#define	MSG_EOF		0x100 /* data completes transaction */
+#define	MSG_OOB		0x00001 /* process out-of-band data */
+#define	MSG_PEEK	0x00002 /* peek at incoming message */
+#define	MSG_DONTROUTE	0x00004 /* bypass routing, use direct interface */
+#define MSG_EOR		0x00008 /* data completes record */
+#define	MSG_EOF		0x00100 /* data completes transaction */
+#define	MSG_NOSIGNAL	0x20000 /* do not generate SIGPIPE on EOF */
 .Ed
 .Pp
 The flag
@@ -135,6 +136,9 @@ protocol family, and is used to implement Transaction
 .Xr ttcp 4 ) .
 .Dv MSG_DONTROUTE
 is usually used only by diagnostic or routing programs.
+.Dv MSG_NOSIGNAL
+is used to prevent SIGPIPE generation when writing a socket that
+may be closed.
 .Pp
 See
 .Xr recv 2

sys/sys/param.h

@@ -57,7 +57,7 @@
  *		is created, otherwise 1.
  */
 #undef __FreeBSD_version
-#define __FreeBSD_version 600019	/* Master, propagated to newvers */
+#define __FreeBSD_version 600020	/* Master, propagated to newvers */
 
 #ifndef LOCORE
 #include <sys/types.h>

sys/sys/socket.h

@@ -398,7 +398,9 @@ struct msghdr {
 #endif
 #ifdef _KERNEL
 #define	MSG_SOCALLBCK   0x10000		/* for use by socket callbacks - soreceive (TCP) */
-#define	MSG_NOSIGNAL	0x20000		/* for use with emulation layers */
+#endif
+#if __BSD_VISIBLE
+#define	MSG_NOSIGNAL	0x20000		/* do not generate SIGPIPE on EOF */
 #endif
 
 /*