how to control 32 com port through application

Dear Sir,
i m going to use NP5610-16 moxa device for multiport serial communication.
i m using fedora-core 6 o.s.
i m using qt-3.3.8 on fedora 6
after installation it will detect serial ports as /dev/ttyr0,/dev/ttyr1 .....etc
now i want to write application which monitor all serial ports and received data from particular serial ports.
after that it send data on particular port.
its ok i understand this concept.
but i confuse that what programming approach i have to use to monitor multiport serial ports.
i have to fire 16 diff threads for each port or what
plz help me to sort out this issue
please also guide me that which is the best approach i have to use for this
Regards,
Amit