Split out mmap's compatibility flags into a separate section, so users

aren't misled into thinking they're useful on OpenBSD.

1 files changed, 33 insertions, 15 deletions

diff --git a/lib/libc/sys/mmap.2 b/lib/libc/sys/mmap.2
index 37161ec5371..fa28d108e6f 100644
--- a/lib/libc/sys/mmap.2
+++ b/lib/libc/sys/mmap.2
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: mmap.2,v 1.45 2014/06/27 19:02:54 matthew Exp $
+.\"	$OpenBSD: mmap.2,v 1.46 2014/06/27 19:26:36 matthew Exp $
 .\"	$NetBSD: mmap.2,v 1.5 1995/06/24 10:48:59 cgd Exp $
 .\"
 .\" Copyright (c) 1991, 1993
@@ -135,9 +135,6 @@ The file descriptor used for creating
 .Dv MAP_ANON
 must currently be \-1 indicating no name is associated with the
 region.
-.It Dv MAP_FILE
-Mapped from a regular file or character-special device memory.
-(This is the default mapping type, and need not be specified.)
 .It Dv MAP_FIXED
 Demand that the mapping is placed at
 .Fa addr ,
@@ -152,27 +149,48 @@ mappings)
 must be multiples of the page size.
 Existing mappings in the address range will be replaced.
 Use of this option is discouraged.
+.El
+.Pp
+Finally, the following flags are also provided for
+source compatibility with code written for other operating systems,
+but are not recommended for use in new
+.Ox
+code:
+.Bl -tag -width MAP_PRIVATE -offset indent
+.It Dv MAP_COPY
+Modifications are private and, unlike
+.Dv MAP_PRIVATE ,
+modifications made by others are not visible.
+(On
+.Ox ,
+this behaves just like
+.Dv MAP_PRIVATE ).
+.It Dv MAP_FILE
+Mapped from a regular file or character-special device memory.
+(On
+.Ox
+and all systems conforming to
+.St -p1003.1-2008 ,
+this is the default mapping type, and need not be specified.)
 .It Dv MAP_HASSEMAPHORE
 Notify the kernel that the region may contain semaphores and that special
 handling may be necessary.
+(On
+.Ox ,
+this flag is ignored.)
 .It Dv MAP_INHERIT
 Permit regions to be inherited across
 .Xr exec 3
 system calls.
+(On
+.Ox ,
+this flag is ignored.)
 .It Dv MAP_TRYFIXED
 Attempt to use the hint provided by
 .Fa addr .
-This is the default mapping type and need not be specified.
-Use of
-.Dv MAP_TRYFIXED
-is discouraged, as it is a non-portable extension.
-.It Dv MAP_COPY
-Modifications are private and, unlike
-.Dv MAP_PRIVATE ,
-modifications made by others are not visible.
-This option is deprecated, shouldn't be used and behaves just like
-.Dv MAP_PRIVATE
-in the current implementation.
+(On
+.Ox ,
+this is the default behavior.)
 .El
 .Pp
 The