ftype(p1)
public
Identifies the type of the named file; the return string is one of “file”, “directory”, “characterSpecial”, “blockSpecial”, “fifo”, “link”, “socket”, or “unknown”.
File.ftype("testfile") #=> "file" File.ftype("/dev/tty") #=> "characterSpecial" File.ftype("/tmp/.X11-unix/X0") #=> "socket"