// If the signal handler receives a SIGPROF signal on a non-Go thread,
// it tries to collect a traceback into sigprofCallers.
// sigprofCallersUse is set to non-zero while sigprofCallers holds a traceback.
var sigprofCallers cgoCallers
var sigprofCallersUse uint32

// sigprofNonGo is called if we receive a SIGPROF signal on a non-Go thread,
// and the signal handler collected a stack trace in sigprofCallers.

	} else if ret := cgocaller(cgo_libc_setgid, uintptr(gid)); ret != 0 {
		err = errnoErr(Errno(ret))
	}
	return
}

var cgo_libc_setregid unsafe.Pointer // non-nil if cgo linked.

func Setregid(rgid, egid int) (err error) {
	if cgo_libc_setregid == nil {
		if _, _, e1 := AllThreadsSyscall(sys_SETREGID, uintptr(rgid), uintptr(egid), 0); e1 != 0 {
			err = errnoErr(e1)
		}