Kontron KTAM3874-pITX - Manual (Page 272)

KTD-S0057-I Page 268 Linux® Programming Examples (DebianTM)
KTAM3874/pITX Software Guide
int main (void)
{
int fifo_rd, fifo_wr, value;
pid_t pid;
static char buff_rd [RD_SIZE];
static char buff_wr [WR_SIZE];
/* Fork off the parent process */
if ((pid = fork ()) < 0)
ERROR;
/* If we got a good PID then we can exit the parent process */
if (pid > 0)
exit (EXIT_SUCCESS);
/* process becomes session leader, group leader and has no controlling shell */
if (setsid () < 0)
ERROR;
signal (SIGHUP, signal_handler);
signal (SIGTERM, signal_handler);
get_mask (1);
if (mkfifo (root_rd, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP | S_IWOTH | S_IROTH) < 0)
{
umask (get_mask (0));
ERROR;
}
if (mkfifo (root_wr, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP | S_IWOTH | S_IROTH) < 0)
{
unlink (root_rd);
umask (get_mask (0));
ERROR;
}
oldmask = umask (0);
if ((fifo_rd = open (root_rd, O_RDONLY)) < 0 || (fifo_wr = open (root_wr, O_WRONLY)) < 0)
{
unlink (root_rd);
unlink (root_wr);
umask (get_mask (0));
ERROR;
}
while (read (fifo_rd, buff_rd, RD_SIZE) > 0)
{
if (!strncasecmp (buff_rd, CMD_WDIO, CMD_SIZE))
{
if (!parse_wdio (buff_rd))
write (fifo_wr, ACK_STR, ACK_SIZE);
else
write (fifo_wr, NAK_STR, NAK_SIZE);
}