Golang 执行shell命令
Golang 执行shell命令
参考:
go语言执行外部程序-标准库os/exec使用举例
https://blog.csdn.net/hsy12342611/article/details/131478879
go语言执行系统命令 - 标准库os/exec详解
https://blog.csdn.net/weixin_49393427/article/details/116693536
golang 执行shell命令大全
1. 执行命令并获得输出结果
CombinedOutput() 返回 standard output and standard error
func main() { cmd := exec.Command("ls", "-lah") out, err := cmd.CombinedOutput() if err != nil { log.Fatalf("cmd.Run() failed with %s\n", err) } fmt.Printf("combined out:\n%s\n", string(out)) }
Output() 返回standard output
func main() { out, err := exec.Command("date").Output() if err != nil { log.Fatal(err) } fmt.Printf("The date is %s\n", out) }
2. 将stdout和stderr分别处理
用buffer接受输出
func main() { cmd := exec.Command("ls", "-lah") var stdin, stdout, stderr bytes.Buffer cmd.Stdin = &stdin cmd.Stdout = &stdout cmd.Stderr = &stderr err := cmd.Run() if err != nil { log.Fatalf("cmd.Run() failed with %s\n", err) } outStr, errStr := string(stdout.Bytes()), string(stderr.Bytes()) fmt.Printf("out:\n%s\nerr:\n%s\n", outStr, errStr) }
直接终端打印输出
func main() { cmd := exec.Command("ls", "-lah") cmd.Stdout = os.Stdout cmd.Stderr = os.Stdout err := cmd.Run() if err != nil { log.Fatalf("cmd.Run() failed with %s\n", err) } }
3. 异步执行命令
cmd.Run() 阻塞等待命令执行结束
cmd.Start() 不会等待命令完成
package main import ( "bytes" "fmt" "io" "log" "os" "os/exec" ) func main() { var stdoutBuf, stderrBuf bytes.Buffer cmd := exec.Command("bash", "-c", "for i in 1 2 3 4;do echo $i;sleep 2;done") stdoutIn, _ := cmd.StdoutPipe() stderrIn, _ := cmd.StderrPipe() var errStdout, errStderr error stdout := io.MultiWriter(os.Stdout, &stdoutBuf) stderr := io.MultiWriter(os.Stderr, &stderrBuf) err := cmd.Start() if err != nil { log.Fatalf("cmd.Start() failed with '%s'\n", err) } go func() { _, errStdout = io.Copy(stdout, stdoutIn) }() go func() { _, errStderr = io.Copy(stderr, stderrIn) }() err = cmd.Wait() if err != nil { log.Fatalf("cmd.Run() failed with %s\n", err) } if errStdout != nil || errStderr != nil { log.Fatal("failed to capture stdout or stderr\n") } outStr, errStr := string(stdoutBuf.Bytes()), string(stderrBuf.Bytes()) fmt.Printf("\nout:\n%s\nerr:\n%s\n", outStr, errStr) }
4. 执行时带上环境变量
func main() { cmd := exec.Command("bash", "-c", "programToExecute") additionalEnv := "programToExecute=ls" newEnv := append(os.Environ(), additionalEnv) cmd.Env = newEnv out, err := cmd.CombinedOutput() if err != nil { log.Fatalf("cmd.Run() failed with %s\n", err) } fmt.Printf("%s", out) }
5. 预先检查命令是否存在
func checkLsExists() { path, err := exec.LookPath("ls") if err != nil { fmt.Printf("didn't find 'ls' executable\n") } else { fmt.Printf("'ls' executable is in '%s'\n", path) } }
6. 两个命令依次执行,管道通信
func main() { c1 := exec.Command("ls") c2 := exec.Command("wc", "-l") r, w := io.Pipe() c1.Stdout = w c2.Stdin = r var b2 bytes.Buffer c2.Stdout = &b2 c1.Start() c2.Start() c1.Wait() w.Close() c2.Wait() io.Copy(os.Stdout, &b2) }
或者
func main() { c1 := exec.Command("ls") c2 := exec.Command("wc", "-l") c2.Stdin, _ = c1.StdoutPipe() c2.Stdout = os.Stdout _ = c2.Start() _ = c1.Run() _ = c2.Wait() }
错误方式
c := exec.Command("ls", "|", "wc", "-l") c.Stdout = os.Stdout _ = c.Run()
可以用 bash -c 或者 sh -c
func main() { cmd := "cat /proc/cpuinfo | egrep '^model name' | uniq | awk '{print substr($0, index($0,$4))}'" out, err := exec.Command("bash", "-c", cmd).Output() if err != nil { fmt.Printf("Failed to execute command: %s", cmd) } fmt.Println(string(out)) }
7. 按行读取输出内容
func main() { cmd := exec.Command("ls", "-la") stdout, _ := cmd.StdoutPipe() cmd.Start() reader := bufio.NewReader(stdout) for { line, err := reader.ReadString('\n') line = strings.TrimSpace(line) if err != nil || io.EOF == err { break } log.Println(line) } cmd.Wait() }
8. 获得exit code
func RunCommand(name string, args ...string) (stdout string, stderr string, exitCode int) { log.Println("run command:", name, args) var outbuf, errbuf bytes.Buffer cmd := exec.Command(name, args...) cmd.Stdout = &outbuf cmd.Stderr = &errbuf err := cmd.Run() stdout = outbuf.String() stderr = errbuf.String() if err != nil { // try to get the exit code if exitError, ok := err.(*exec.ExitError); ok { ws := exitError.Sys().(syscall.WaitStatus) exitCode = ws.ExitStatus() } else { // This will happen (in OSX) if `name` is not available in $PATH, // in this situation, exit code could not be get, and stderr will be // empty string very likely, so we use the default fail code, and format err // to string and set to stderr log.Printf("Could not get exit code for failed program: %v, %v", name, args) exitCode = defaultFailedCode if stderr == "" { stderr = err.Error() } } } else { // success, exitCode should be 0 if go is ok ws := cmd.ProcessState.Sys().(syscall.WaitStatus) exitCode = ws.ExitStatus() } log.Printf("command result, stdout: %v, stderr: %v, exitCode: %v", stdout, stderr, exitCode) return }