Moved Pipe{} into own sub-package

It may be moved into a separate project at some point, who knows...

unixutils/pipe.go

@@ -0,0 +1,80 @@
+//
+// Copyright 2014-2016 Cristian Maglie. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+//
+
+// +build linux darwin freebsd
+
+package unixutils // import "go.bug.st/serial.v1/unixutils"
+
+import "syscall"
+import "fmt"
+
+// Pipe represents a unix-pipe
+type Pipe struct {
+	opened bool
+	rd     int
+	wr     int
+}
+
+// Open creates a new pipe
+func (p *Pipe) Open() error {
+	fds := []int{0, 0}
+	if err := syscall.Pipe(fds); err != nil {
+		return err
+	}
+	p.rd = fds[0]
+	p.wr = fds[1]
+	p.opened = true
+	return nil
+}
+
+// ReadFD returns the file handle for the read side of the pipe.
+func (p *Pipe) ReadFD() int {
+	if !p.opened {
+		return -1
+	}
+	return p.rd
+}
+
+// WriteFD returns the flie handle for the write side of the pipe.
+func (p *Pipe) WriteFD() int {
+	if !p.opened {
+		return -1
+	}
+	return p.wr
+}
+
+// Write to the pipe the content of data. Returns the numbre of bytes written.
+func (p *Pipe) Write(data []byte) (int, error) {
+	if !p.opened {
+		return 0, fmt.Errorf("Pipe not opened")
+	}
+	return syscall.Write(p.wr, data)
+}
+
+// Read from the pipe into the data array. Returns the number of bytes read.
+func (p *Pipe) Read(data []byte) (int, error) {
+	if !p.opened {
+		return 0, fmt.Errorf("Pipe not opened")
+	}
+	return syscall.Read(p.rd, data)
+}
+
+// Close the pipe
+func (p *Pipe) Close() error {
+	if !p.opened {
+		return fmt.Errorf("Pipe not opened")
+	}
+	err1 := syscall.Close(p.rd)
+	err2 := syscall.Close(p.wr)
+	p.opened = false
+	if err1 != nil {
+		return err1
+	}
+	if err2 != nil {
+		return err2
+	}
+	return nil
+}