Read and write from a device connected through USB to PC

Hi All,
Is there any APIs in QNX, which can be used to read and write the data from a device which is connected to PC through USB cable.

This device is a storage device which has magnetic disks inside.

I want to read the data sector wise, each sector is of 512 blocks in size.

Thank you All in advance.

open ( “/dev/umass0” …
read()
write()
close()