Kontron KTAM3874-pITX - Manual (Page 268)

KTD-S0057-I Page 264 Linux® Programming Examples (DebianTM)
KTAM3874/pITX Software Guide
if (!gp_dir)
{
if (read (fd_io, str, sizeof (str)) < 0)
return -1;
str [1] = '\0';
*val = atoi (str);
return lseek (fd_io, 0, SEEK_SET);
}
else
{
if (param3 != (char *) NULL)
{
if (strcasecmp (param3, IO_LOW) && strcasecmp (param3, IO_HIGH))
return -1;
}
if (write (fd_io, param3, strlen (param3)) != strlen (param3))
return -1;
return lseek (fd_io, 0, SEEK_SET);
}
}
return -1;
}
int main (void)
{
int fifo_rd, fifo_wr, value;
mode_t oldmask = umask (0);
static char buff_rd [RD_SIZE];
static char buff_wr [WR_SIZE];
if (mkfifo (root_rd, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP | S_IWOTH | S_IROTH) < 0)
{
umask (oldmask);
ERROR;
}
if (mkfifo (root_wr, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP | S_IWOTH | S_IROTH) < 0)
{
unlink (root_rd);
umask (oldmask);
ERROR;
}
if ((fifo_rd = open (root_rd, O_RDONLY)) < 0 || (fifo_wr = open (root_wr, O_WRONLY)) < 0)
{
unlink (root_rd);
unlink (root_wr);
umask (oldmask);
ERROR;
}