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clockctl(4) vs settimeofday(2)

According to the clockctl(4) man page, operations on system time should
first try the /dev/clockctl device, and only fall-back to the syscall()
if the device is not available:

	... The system call stubs in C library will use the ioctl(2) on
	/dev/clockctl if the special file is present and accessible, or
	will revert to the plain super-user-restricted system call if
	the special file is not accessible.

However, looking at the source file for lib/libc/sys/settimeofday.c we
have the following comment which says that we first try the syscall()
and only use the /dev/clockctl mechanism if the syscall() fails:

settimeofday(const struct timeval *tv, const void *tzp)
        struct clockctl_settimeofday args;
        int rv;

         * try syscal first and attempt to switch to clockctl
         * if that fails with EPERM

Which of these is correct?  And which needs to be updated?


| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:      |
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