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package main // import "github.com/tianon/gosu"
import (
"log"
"os"
"os/exec"
"path/filepath"
"runtime"
"strings"
"syscall"
)
func init() {
// make sure we only have one process and that it runs on the main thread (so that ideally, when we Exec, we keep our user switches and stuff)
runtime.GOMAXPROCS(1)
runtime.LockOSThread()
}
func main() {
log.SetFlags(0) // no timestamps on our logs
if len(os.Args) <= 2 {
self := filepath.Base(os.Args[0])
log.Printf("Usage: %s user-spec command [args]", self)
log.Printf(" ie: %s tianon bash", self)
log.Printf(" %s nobody:root bash -c 'whoami && id'", self)
log.Printf(" %s 1000:1 id", self)
log.Println()
log.Printf("%s version: %s (%s on %s/%s; %s)", self, Version, runtime.Version(), runtime.GOOS, runtime.GOARCH, runtime.Compiler)
log.Printf("%s license: GPL-3 (full text at https://github.com/tianon/gosu)\n", strings.Repeat(" ", len(self)))
log.Println()
os.Exit(1)
}
// clear HOME so that SetupUser will set it
os.Unsetenv("HOME")
if err := SetupUser(os.Args[1]); err != nil {
log.Fatalf("error: failed switching to %q: %v", os.Args[1], err)
}
name, err := exec.LookPath(os.Args[2])
if err != nil {
log.Fatalf("error: %v", err)
}
if err = syscall.Exec(name, os.Args[2:], os.Environ()); err != nil {
log.Fatalf("error: exec failed: %v", err)
}
}
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