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.
@item
This function returns a bogus value instead of failing with
@code{ENOSYS} on some platforms:
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:
@item
Some platforms lack the ability to change the timestamps of a file
descriptor, so the replacement can fail with @code{ENOSYS}; the gnulib
-module @samp{utimens} provides a more reliable interface @code{gl_futimens}.
+module @samp{utimens} provides a more reliable interface @code{fdutimens}.
+@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