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10.57.6 futimens ¶

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/futimens.html

Gnulib module: futimens

Portability problems fixed by Gnulib:

• This function is missing on some platforms: glibc 2.5, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.3. However, the replacement function may end up truncating timestamps to worse resolution than supported by the file system.
• This function returns a bogus value instead of failing with ENOSYS on some platforms: Linux kernel 2.6.21.
• When using UTIME_OMIT or UTIME_NOW, some systems require the 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.
• When using UTIME_OMIT for the modification time, but specifying an access time, some systems fail to update the change time: Linux kernel 2.6.32, macOS 14, NetBSD 10.0, Solaris 11.1.
• Passing AT_FDCWD as the fd argument does not properly fail with EBADF on some systems: glibc 2.11, musl libc, Solaris 11.

Portability problems not fixed by Gnulib:

• On file systems mounted with the noatime attribute, this function might not modify the access time as requested: Linux kernel 6.9.
• This function sets a slightly different time stamp than the requested one: Haiku.
• Some platforms lack the ability to change the timestamps of a file descriptor, so the replacement can fail with ENOSYS; the gnulib module ‘utimens’ provides a more reliable interface fdutimens.
• The mere act of using stat modifies the access time of directories on some platforms, so utimensat can only effectively change directory modification time: Cygwin 1.5.x.