// want that to cause an "unexpected files" failure at the end of the run.
	cmd.Env = append(slices.Clip(tg.env), tempEnvName()+"="+t.TempDir())

	cmd.SysProcAttr = &syscall.SysProcAttr{
		Setpgid: true,
	}
	cmd.Cancel = func() error {
		pgid := cmd.Process.Pid
		return syscall.Kill(-pgid, syscall.SIGINT)
	}

	pipe, err := cmd.StdoutPipe()
	if err != nil {
		t.Fatal(err)
	}

//sys	Select(n int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (err error)
//sysnb	Setegid(egid int) (err error)
//sysnb	Seteuid(euid int) (err error)
//sysnb	Setgid(gid int) (err error)
//sys	Setlogin(name string) (err error)
//sysnb	Setpgid(pid int, pgid int) (err error)
//sys	Setpriority(which int, who int, prio int) (err error)
//sysnb	Setregid(rgid int, egid int) (err error)
//sysnb	Setreuid(ruid int, euid int) (err error)

//sys	Select(n int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (err error)
//sysnb	Setegid(egid int) (err error)
//sysnb	Seteuid(euid int) (err error)
//sysnb	Setgid(gid int) (err error)
//sys	Setlogin(name string) (err error)
//sysnb	Setpgid(pid int, pgid int) (err error)
//sys	Setpriority(which int, who int, prio int) (err error)
//sysnb	Setregid(rgid int, egid int) (err error)
//sysnb	Setreuid(ruid int, euid int) (err error)

		filter, expect string
	}{
		{call: "Setegid(1)", fn: func() error { return syscall.Setegid(1) }, filter: "Gid:", expect: "\t0\t1\t0\t1"},
		{call: "Setegid(0)", fn: func() error { return syscall.Setegid(0) }, filter: "Gid:", expect: "\t0\t0\t0\t0"},

		{call: "Seteuid(1)", fn: func() error { return syscall.Seteuid(1) }, filter: "Uid:", expect: "\t0\t1\t0\t1"},

  } else                           \
    x->retval = ret

void
_cgo_libc_setegid(argset_t* x) {
	SET_RETVAL(setegid((gid_t) x->args[0]));
}

void
_cgo_libc_seteuid(argset_t* x) {
	SET_RETVAL(seteuid((uid_t) x->args[0]));
}

void
_cgo_libc_setgid(argset_t* x) {
	SET_RETVAL(setgid((gid_t) x->args[0]));
}

void
_cgo_libc_setgroups(argset_t* x) {

	Threads    int    `json:"threads"`
	Goroutines int    `json:"goroutines"`
}

func getProcInfo() *procInfo {
	pi := procInfo{
		Egid:       os.Getegid(),
		Euid:       os.Geteuid(),
		GID:        os.Getgid(),
		Pid:        os.Getpid(),
		Ppid:       os.Getppid(),
		UID:        os.Getuid(),
		TempDir:    os.TempDir(),
		Goroutines: runtime.NumGoroutine(),
	}

	pi.Groups, _ = os.Getgroups()

// Test that setgid does not hang on Linux.
// See https://golang.org/issue/3871 for details.

package cgotest

/*
#include <sys/types.h>
#include <unistd.h>
*/
import "C"

import (
	"os"
	"os/signal"
	"syscall"
	"testing"
	"time"
)

func runTestSetgid() bool {
	c := make(chan bool)
	go func() {
		C.setgid(0)
		c <- true
	}()
	select {
	case <-c:

	return string(buf[:n]), nil
}

func Getuid() int {
	return jsProcess.Call("getuid").Int()
}

func Getgid() int {
	return jsProcess.Call("getgid").Int()
}

func Geteuid() int {
	return jsProcess.Call("geteuid").Int()
}

func Getegid() int {
	return jsProcess.Call("getegid").Int()
}

func Getgroups() (groups []int, err error) {
	defer recoverErr(&err)

	// Rewind stack pointer so anything that happens on the stack
	// will clobber the test pattern created by the caller
	ADDU	$(1024*8), R29

	// Ask signaller to setgid
	MOVW	$1, R1
	SYNC
	MOVW	R1, ·Baton(SB)
	SYNC

	// Wait for setgid completion
loop:
	SYNC
	MOVW	·Baton(SB), R1
	OR	R2, R2, R2	// hint that we're in a spin loop
	BNE	R1, loop
	SYNC

	// Restore stack
	ADDU	$(-1024*8), R29

	// Rewind stack pointer so anything that happens on the stack
	// will clobber the test pattern created by the caller
	ADD	$(1024 * 8), R1

	// Ask signaller to setgid
	MOVW	$1, R3
	SYNC
	MOVW	R3, ·Baton(SB)

	// Wait for setgid completion
loop:
	SYNC
	MOVW	·Baton(SB), R3
	CMP	R3, $0
	// Hint that we're in a spin loop
	OR	R1, R1, R1
	BNE	loop
	ISYNC

	// Restore stack