golang sockcmsg_dragonfly 代码
文件路径：/src/cmd/vendor/golang.org/x/sys/unix/sockcmsg_dragonfly.go
// Copyright 2019 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package unix
// Round the length of a raw sockaddr up to align it properly.
func cmsgAlignOf(salen int) int {
salign := SizeofPtr
if SizeofPtr == 8 && !supportsABI(_dragonflyABIChangeVersion) {
// 64-bit Dragonfly before the September 2019 ABI changes still requires
// 32-bit aligned access to network subsystem.
salign = 4
}
return (salen + salign - 1) & ^(salign - 1)
}