1 files changed, 58 insertions, 0 deletions
diff --git a/doc/progs/fd.go b/doc/progs/fd.go
new file mode 100644
index 000000000..50d33624a
--- /dev/null
+++ b/doc/progs/fd.go
@@ -0,0 +1,58 @@
+// Copyright 2009 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 fd
+
+import Syscall "syscall"
+
+export type FD struct {
+	fildes	int64;	// file descriptor number
+	name	string;	// file name at Open time
+}
+
+func NewFD(fd int64, name string) *FD {
+	if fd < 0 {
+		return nil
+	}
+	n := new(FD);
+	n.fildes = fd;
+	n.name = name;
+	return n
+}
+
+export var (
+	Stdin  = NewFD(0, "/dev/stdin");
+	Stdout = NewFD(1, "/dev/stdout");
+	Stderr = NewFD(2, "/dev/stderr");
+)
+
+export func Open(name string, mode int64, perm int64) (fd *FD, errno int64) {
+	r, e := Syscall.open(name, mode, perm);
+	return NewFD(r, name), e
+}
+
+func (fd *FD) Close() int64 {
+	if fd == nil {
+		return Syscall.EINVAL
+	}
+	r, e := Syscall.close(fd.fildes);
+	fd.fildes = -1;  // so it can't be closed again
+	return 0
+}
+
+func (fd *FD) Read(b *[]byte) (ret int64, errno int64) {
+	if fd == nil {
+		return -1, Syscall.EINVAL
+	}
+	r, e := Syscall.read(fd.fildes, &b[0], int64(len(b)));
+	return r, e
+}
+
+func (fd *FD) Write(b *[]byte) (ret int64, errno int64) {
+	if fd == nil {
+		return -1, Syscall.EINVAL
+	}
+	r, e := Syscall.write(fd.fildes, &b[0], int64(len(b)));
+	return r, e
+}