Cmd.StdoutPipe, Cmd.StdinPipe, Cmd.StderrPipe all close the client end of the pipe when
Wait returns. This is problematic when there's an independent goroutine that uses the
client end of the pipe. For example, this code can
fail to copy all the data from a command.
c := exec.Command("some-command")
r, err := c.StdoutPipe()
if err != nil {...}
go io.Copy(dest, r)
c.Run()
Since all these methods return io.*Closer types, it seems reasonable to me that the
caller should have the responsibility for closing them.
