Sys.setFileTime {base}R Documentation

Set File Time


Uses system calls to set the times on a file or directory.


Sys.setFileTime(path, time)



A character vector containing file or directory paths.


A date-time of class "POSIXct" or an object which can be coerced to one. Fractions of a second may be ignored. Recycled along paths.


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.

Sys.setFileTime has been vectorized in R 3.6.0. Earlier versions of R required path and time to be vectors of length one.


A logical vector indicating if the operation succeeded for each of the files and directories attempted, returned invisibly.

[Package base version 3.6.0 Index]