Hi, I have a question regarding the mknod command. I use Cygnus to silmulate the Linux in the Windows NT environment. As refer from Linux manual, to create a ttyS0/1 (com1 and com2) file, I need to "mknod -m 660 /dev/ttyS0 c 4 64 # base address 0x03f8 " and "mknod -m 660 /dev/ttyS1 c 4 65 # base address 0x02f8 " However, it returns me the message "Function not implemented" !! Is that any problem with my syntex? Thanks for your help. Regards, kenghua