regex_internal.h: define __attribute_warn_unused_result__

[gnulib.git] / doc / posix-functions / utimensat.texi

diff --git a/doc/posix-functions/utimensat.texi b/doc/posix-functions/utimensat.texi
index 7164965..85fc218 100644 (file)
--- a/doc/posix-functions/utimensat.texi
+++ b/doc/posix-functions/utimensat.texi
@@ -13,15 +13,27 @@ This function is missing on some platforms:
 glibc 2.3.6, MacOS X 10.3, FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, AIX
 5.1, HP-UX 11, IRIX 6.5, OSF/1 5.1, Solaris 10, Cygwin 1.5.x, mingw,
 Interix 3.5, BeOS.
+However, the replacement function may end up truncating timestamps to
+less resolution than supported by the file system.  Furthermore, the
+replacement function is not safe to be used in libraries and is not
+multithread-safe.
 @item
 This function returns a bogus value instead of failing with
 @code{ENOSYS} on some platforms:
 Linux kernel 2.6.21.
 @item
+This function fails with @code{ENOSYS} if passed the flag
+@code{AT_SYMLINK_NOFOLLOW} on a regular file:
+Linux kernel 2.6.22.
+@item
 When using @code{UTIME_OMIT} or @code{UTIME_NOW}, some systems require
 the @code{tv_sec} argument to be 0, and don't necessarily handle all
 file permissions in the manner required by POSIX:
 Linux kernel 2.6.25.
+@item
+When using @code{UTIME_OMIT} for the modification time, but specifying
+an access time, some systems fail to update the change time:
+Linux kernel 2.6.32.
 @end itemize
 
 Portability problems not fixed by Gnulib:
@@ -35,6 +47,11 @@ The mere act of using @code{lstat} modifies the access time of
 symlinks on some platforms, so @code{utimensat} with
 @code{AT_SYMLINK_NOFOLLOW} can only effectively change modification time:
 Cygwin.
+@item
+The mere act of using @code{stat} modifies the access time of
+directories on some platforms, so @code{utimensat} can only
+effectively change directory modification time:
+Cygwin 1.5.x.
 @end itemize
 
-The gnulib module utimens provides a similar interface.
+The gnulib module fdutimensat provides a similar interface.