hi where is the implementation of the system call tcsetattr( )/tcgetattr ( ). What i mean where does it gets mapped to in the kernel code ????? Also I am loookig for implementing RTS /CTS flow control in the serial driver . But i am not able to find any sample implementation in the usr/src/linux/drivers/char ........ Any help is welcome ...... - Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ IRC Channel: irc.openprojects.net / #kernelnewbies Web Page: http://www.kernelnewbies.org/