Uses system calls to set the times on a file or directory.
Sys.setFileTime(path, time)A length-one character vector specifying the path to a file or directory.
A date-time of class "POSIXct" or an object which can
be coerced to one. Fractions of a second may be ignored.
Logical, invisibly. An indication if the operation succeeded.
This attempts sets the file time to the value specified.
On a Unix-alike it uses the system call utimensat if that is
available, otherwise utimes or utime. On a POSIX file
system it sets both the last-access and modification times.
Fractional seconds will set as from R 3.4.0 on OSes with the
requisite system calls and suitable filesystems.
On Windows it uses the system call SetFileTime to set the
‘last write time’. Some Windows file systems only record the
time at a resolution of two seconds.