| unlink {base} | R Documentation | 
unlink deletes the file(s) or directories specified by x.
unlink(x, recursive = FALSE)
x | 
a character vector with the names of the file(s) or directories to be deleted. Wildcards (normally ‘*’ and ‘?’) are allowed. | 
recursive | 
logical. Should directories be deleted recursively? | 
If recursive = FALSE directories are not deleted,
not even empty ones.
file.remove can only remove files, but gives more
detailed error information.
The return value of the corresponding system command, rm -f,
normally 0 for success, 1 for failure.
Not deleting a non-existent file is not a failure.
Prior to R version 1.2.0 the default on Unix was recursive =
    TRUE, and on Windows empty directories could be deleted.
Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) The New S Language. Wadsworth & Brooks/Cole.