1
0
mirror of https://github.com/golang/go synced 2024-11-19 09:44:46 -07:00
go/src/os/exec_plan9.go
Brad Fitzpatrick 871b79316a os: clarify docs on Interrupt and Kill
Note that Interrupt will compile but not work on Windows.

Fixes #22454

Change-Id: If011c32211f4bb45d458317e113b9794d5b4a4b1
Reviewed-on: https://go-review.googlesource.com/81035
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-12-02 02:49:01 +00:00

139 lines
3.0 KiB
Go

// 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 os
import (
"errors"
"runtime"
"syscall"
"time"
)
// The only signal values guaranteed to be present in the os package
// on all systems are Interrupt (send the process an interrupt) and
// Kill (force the process to exit). Interrupt is not implemented on
// Windows; using it with os.Process.Signal will return an error.
var (
Interrupt Signal = syscall.Note("interrupt")
Kill Signal = syscall.Note("kill")
)
func startProcess(name string, argv []string, attr *ProcAttr) (p *Process, err error) {
sysattr := &syscall.ProcAttr{
Dir: attr.Dir,
Env: attr.Env,
Sys: attr.Sys,
}
for _, f := range attr.Files {
sysattr.Files = append(sysattr.Files, f.Fd())
}
pid, h, e := syscall.StartProcess(name, argv, sysattr)
if e != nil {
return nil, &PathError{"fork/exec", name, e}
}
return newProcess(pid, h), nil
}
func (p *Process) writeProcFile(file string, data string) error {
f, e := OpenFile("/proc/"+itoa(p.Pid)+"/"+file, O_WRONLY, 0)
if e != nil {
return e
}
defer f.Close()
_, e = f.Write([]byte(data))
return e
}
func (p *Process) signal(sig Signal) error {
if p.done() {
return errors.New("os: process already finished")
}
if e := p.writeProcFile("note", sig.String()); e != nil {
return NewSyscallError("signal", e)
}
return nil
}
func (p *Process) kill() error {
return p.signal(Kill)
}
func (p *Process) wait() (ps *ProcessState, err error) {
var waitmsg syscall.Waitmsg
if p.Pid == -1 {
return nil, ErrInvalid
}
err = syscall.WaitProcess(p.Pid, &waitmsg)
if err != nil {
return nil, NewSyscallError("wait", err)
}
p.setDone()
ps = &ProcessState{
pid: waitmsg.Pid,
status: &waitmsg,
}
return ps, nil
}
func (p *Process) release() error {
// NOOP for Plan 9.
p.Pid = -1
// no need for a finalizer anymore
runtime.SetFinalizer(p, nil)
return nil
}
func findProcess(pid int) (p *Process, err error) {
// NOOP for Plan 9.
return newProcess(pid, 0), nil
}
// ProcessState stores information about a process, as reported by Wait.
type ProcessState struct {
pid int // The process's id.
status *syscall.Waitmsg // System-dependent status info.
}
// Pid returns the process id of the exited process.
func (p *ProcessState) Pid() int {
return p.pid
}
func (p *ProcessState) exited() bool {
return p.status.Exited()
}
func (p *ProcessState) success() bool {
return p.status.ExitStatus() == 0
}
func (p *ProcessState) sys() interface{} {
return p.status
}
func (p *ProcessState) sysUsage() interface{} {
return p.status
}
func (p *ProcessState) userTime() time.Duration {
return time.Duration(p.status.Time[0]) * time.Millisecond
}
func (p *ProcessState) systemTime() time.Duration {
return time.Duration(p.status.Time[1]) * time.Millisecond
}
func (p *ProcessState) String() string {
if p == nil {
return "<nil>"
}
return "exit status: " + p.status.Msg
}