From 702f62fb48f1cd993cfdfb7d84e17e3874f11635 Mon Sep 17 00:00:00 2001
From: Jilles Tjoelker <jilles@FreeBSD.org>
Date: Sat, 17 Apr 2010 15:52:50 +0000
Subject: [PATCH] getcwd(3): Clarify that EACCES may or may not be checked.

POSIX permits but does not require checking access on the current and parent
directories.

Because various programs do not like it if getcwd(3) fails, it seems best
to avoid checking access as much as possible. There are various reports in
GNATS about this (search for getcwd).

Our getcwd(3) implementation first queries the kernel for the pathname
directly, which does not check any permissions but sometimes fails, and then
falls back to reading all parent directories for the names.

PR:		standards/44425
MFC after:	2 weeks
---
 lib/libc/gen/getcwd.3 | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/lib/libc/gen/getcwd.3 b/lib/libc/gen/getcwd.3
index 12a2bd664af..88291c3e2ee 100644
--- a/lib/libc/gen/getcwd.3
+++ b/lib/libc/gen/getcwd.3
@@ -28,7 +28,7 @@
 .\"     @(#)getcwd.3	8.2 (Berkeley) 12/11/93
 .\" $FreeBSD$
 .\"
-.Dd November 24, 1997
+.Dd April 17, 2010
 .Dt GETCWD 3
 .Os
 .Sh NAME
@@ -108,8 +108,6 @@ The
 function
 will fail if:
 .Bl -tag -width Er
-.It Bq Er EACCES
-Read or search permission was denied for a component of the pathname.
 .It Bq Er EINVAL
 The
 .Fa size
@@ -124,6 +122,16 @@ The
 argument is greater than zero but smaller than the length of the pathname
 plus 1.
 .El
+.Pp
+The
+.Fn getcwd
+function
+may fail if:
+.Bl -tag -width Er
+.It Bq Er EACCES
+Read or search permission was denied for a component of the pathname.
+This is only checked in limited cases, depending on implementation details.
+.El
 .Sh SEE ALSO
 .Xr chdir 2 ,
 .Xr fchdir 2 ,