Golang processes

From wikinotes
Revision as of 04:26, 20 June 2022 by Will (talk | contribs)

TODO:

  • signal handling
  • safely reading from stdin
  • piping outputs to inputs
  • what about exit codes?

Documentation

os https://pkg.go.dev/os@go1.18.3

Current Process

import "os"
import "os/user"

os.Executable()
os.Getpid()
os.Getppid()
os.Getuid()
os.Getgid()

os.Exit(1)              // exit process with exitcode '1'

// environment
envvars := os.Environ() // ["FOO=bar", "BAR=baz", ...]
pwd, err := os.Getwd()  // get current pwd/cwd
user.Current()          // 'will'

Manage Processes

import "syscall"
import "os"
import "os/signal"

proc := os.Process.FindProcess(1234)  // find process with pid
proc.Kill()                           // kill process (-9/SIGKILL)
proc.Signal(os.Iterrupt)              // send SIGINT to process (looks like you can use any syscall.SIG*)
proc.Wait()                           // wait for process to end

syscall.Kill(1234, syscall.SIGINT)    // send SIGINT to pid 1234

Subprocess

import "os"
import "os/exec"

os.StartProcess // todo

cmd := exec.Command("netstat", "-an")
stdout, err := cmd.Output()

reader, err := cmd.StderrPipe()
reader, err := cmd.StdoutPipe()
writer, err := cmd.StdinPipe()

err := cmd.Run()   // run and wait
err := cmd.Start() // run, don't wait
err := cmd.Wait()  // wait for proces to finish

Process Info