support compiling on darwin

splice/pair_darwin.go

@@ -4,19 +4,18 @@
 
 package splice
 
-import ()
-
 func (p *Pair) LoadFromAt(fd uintptr, sz int, off int64) (int, error) {
 	panic("not implemented")
-	return 0, nil
 }
 
 func (p *Pair) LoadFrom(fd uintptr, sz int) (int, error) {
 	panic("not implemented")
-	return 0, nil
 }
 
 func (p *Pair) WriteTo(fd uintptr, n int) (int, error) {
 	panic("not implemented")
-	return 0, nil
+}
+
+func (p *Pair) discard() {
+	panic("not implemented")
 }

splice/splice.go

@@ -71,12 +71,6 @@ func fcntl(fd uintptr, cmd int, arg int) (val int, errno syscall.Errno) {
 const F_SETPIPE_SZ = 1031
 const F_GETPIPE_SZ = 1032
 
-func osPipe() (int, int, error) {
-	var fds [2]int
-	err := syscall.Pipe2(fds[:], syscall.O_NONBLOCK)
-	return fds[0], fds[1], err
-}
-
 func newSplicePair() (p *Pair, err error) {
 	p = &Pair{}
 	p.r, p.w, err = osPipe()

splice/splice_darwin.go

@@ -0,0 +1,7 @@
+package splice
+
+import "fmt"
+
+func osPipe() (int, int, error) {
+	return 0, 0, fmt.Errorf("not implemented")
+}

splice/splice_linux.go

@@ -0,0 +1,9 @@
+package splice
+
+import "syscall"
+
+func osPipe() (int, int, error) {
+	var fds [2]int
+	err := syscall.Pipe2(fds[:], syscall.O_NONBLOCK)
+	return fds[0], fds[1], err
+}