Hello any body, i new in the forum and i have a cuestion.

I write a program in C from red data form the serial port, i use the Linux Serial Programing How To, the data i read is asyncronus an i use singal from read data when it , the exaple in the how to work fine, but when i open more the one port i not can determine who file descriptor generate the signal in its case SIGIO, the porcion of the code its.
.
.
/* It is one from port */
saio.sa_handler = handler;
saio.sa_mask = 0;
saio.sa_flags = 0;
saio.sa_restorer = NULL;
sigaction(SIGIO,&saio,NULL)
.
.


void handler(){
read_data(fd);
}

thanks

Excusme my English

have you considered looking into:
(1) whether or not it supports select (I doubt it)
(2) using threads & busy-wait

if 2 is an option: remember to sleep in the loop. I suggest with increasing durations, eventually hitting a constant upper bound.

hth --Jonas