HelenOS sources

I8259_OCW3_READ_ISR  157 kernel/genarch/src/drivers/i8259/i8259.c 	pio_write_8(&saved_pic0->port1, I8259_OCW3 | I8259_OCW3_READ_ISR);
I8259_OCW3_READ_ISR  158 kernel/genarch/src/drivers/i8259/i8259.c 	pio_write_8(&saved_pic1->port1, I8259_OCW3 | I8259_OCW3_READ_ISR);
HelenOS homepage, sources at GitHub