container: remove setup pipe helper

The API forces use of finalizer to close the read end of the setup pipe, which is no longer considered acceptable. Exporting this as part of package container also imposes unnecessary maintenance burden.

Signed-off-by: Ophestra <cat@gensokyo.uk>

container/params.go

@@ -8,17 +8,6 @@ import (
 	"syscall"
 )
 
-// Setup appends the read end of a pipe for setup params transmission and returns its fd.
-func Setup(extraFiles *[]*os.File) (int, *os.File, error) {
-	if r, w, err := os.Pipe(); err != nil {
-		return -1, nil, err
-	} else {
-		fd := 3 + len(*extraFiles)
-		*extraFiles = append(*extraFiles, r)
-		return fd, w, nil
-	}
-}
-
 var (
 	ErrReceiveEnv = errors.New("environment variable not set")
 )