From 91243dad42a7a62df73e3b1dfbb810adc1b8b654 Mon Sep 17 00:00:00 2001 From: Michael Kerrisk Date: Thu, 14 Nov 2019 13:00:01 +0100 Subject: [PATCH] mmap.2: Some rewording of the description of MAP_STACK Reword a little to allow for the fact that there are now *two* reasons to consider using this flag. Signed-off-by: Michael Kerrisk --- man2/mmap.2 | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/man2/mmap.2 b/man2/mmap.2 index f7e6f4fdf..b59935fa9 100644 --- a/man2/mmap.2 +++ b/man2/mmap.2 @@ -404,10 +404,13 @@ is supported for private mappings only since Linux 2.6.23. Allocate the mapping at an address suitable for a process or thread stack. .IP -This flag is currently a no-op, -but is used in the glibc threading implementation so that -if some architectures require special treatment for stack allocations, -support can later be transparently implemented for glibc. +This flag is currently a no-op on Linux. +However, by employing this flag, applications can ensure that +they transparently obtain support if the flag +is implemented in the future. +Thus, it is used in the glibc threading implementation to allow for +the fact that some architectures may (later) require special treatment +for stack allocations. .\" See http://lwn.net/Articles/294642 "Tangled up in threads", 19 Aug 08 .\" commit cd98a04a59e2f94fa64d5bf1e26498d27427d5e7 .\" http://thread.gmane.org/gmane.linux.kernel/720412