rem: set_timer( hash_table, &rb->retr_timer, RT_T1_TO_1 ); set_timer( hash_table, &rb->fr_timer, FR_TIMER_LIST );
add: set_timer( &rb->retr_timer, RT_T1_TO_1 ); set_timer( &rb->fr_timer, FR_TIMER_LIST );
context: void start_retr( struct retr_buf *rb ){	rb->retr_list=RT_T1_TO_1;	set_timer( hash_table, &rb->retr_timer, RT_T1_TO_1 );	set_timer( hash_table, &rb->fr_timer, FR_TIMER_LIST );}