how to wait for more than one signal in one task in RTX51 TIny

Hi:

I want to excute one task that is already waiting for serval different signals. how can I do that in the RTX51 TINNY?

for example:
void task_0(){

os_send_signal (2);
}

void task_1(){

os_send_signal (2);
}

void task_2(){

os_wait(K_SIG,0,0); //I want to excute this task until both task_0 and task_1 send the signal to task_2.

++count;

}

//It is expressed in C language :
if( signal_A && signal_B){
task_2();
//how can I send signal_A and signal_B from different tasks to task_2?
}

thanks in advance