1 // Copyright 2013 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 package os 6 7 import "syscall" 8 9 // Pipe returns a connected pair of Files; reads from r return bytes written to w. 10 // It returns the files and an error, if any. 11 func Pipe() (r *File, w *File, err error) { 12 var p [2]int 13 14 e := syscall.Pipe2(p[0:], syscall.O_CLOEXEC) 15 // pipe2 was added in 2.6.27 and our minimum requirement is 2.6.23, so it 16 // might not be implemented. 17 if e == syscall.ENOSYS { 18 // See ../syscall/exec.go for description of lock. 19 syscall.ForkLock.RLock() 20 e = syscall.Pipe(p[0:]) 21 if e != nil { 22 syscall.ForkLock.RUnlock() 23 return nil, nil, NewSyscallError("pipe", e) 24 } 25 syscall.CloseOnExec(p[0]) 26 syscall.CloseOnExec(p[1]) 27 syscall.ForkLock.RUnlock() 28 } else if e != nil { 29 return nil, nil, NewSyscallError("pipe2", e) 30 } 31 32 return NewFile(uintptr(p[0]), "|0"), NewFile(uintptr(p[1]), "|1"), nil 33 } 34