@node utimes
@subsection @code{utimes}
@findex utimes

POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9799919799/functions/utimes.html}

Gnulib module: ---

Portability problems fixed by Gnulib:
@itemize
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
Minix 3.1.8, mingw, MSVC 14.
@item
On some platforms, this function mis-handles a trailing slash:
FreeBSD 7.2, Solaris 9.
@item
This function cannot set full timestamp resolution.  In particular,
some platforms incorrectly round rather than truncate.
@mindex utimens
Use @code{utimensat(AT_FDCWD,file,times,0)},
or the gnulib module @code{utimens},
instead.
@item
On file systems mounted with the @code{noatime} attribute,
this function might not modify the access time as requested:
Linux kernel 6.9.
@item
On some platforms, @code{utimes (file, NULL)} fails to set the
file's timestamp to the current time:
glibc 2.3.3.
@item
On some platforms, @code{utimes} failed on read-only files when
@code{utime} worked fine.
glibc 2.2.5.
@item
This function sets a slightly different time stamp than the requested one:
@c https://dev.haiku-os.org/ticket/19214
Haiku.
@item
On OS/2, this function cannot set the timestamp to earlier than the
year 1980 in local time.
@item
On OS/2, this function cannot set the timestamp to an odd number of
seconds.
@item
On OS/2, this function does not work on an opened file.
@end itemize

@mindex utimens
Extension: Gnulib provides a module @samp{utimens} that works around these
problems and allows to set the time with nanosecond resolution (as far as
supported by the file system).
