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| #include <unistd.h>
#include <stdlib.h>
#include <strings.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <termios.h>
#include <stdio.h>
#define BAUDRATE B9600
#define MODEMDEVICE "/dev/ttyUSB0"
#define _POSIX_SOURCE 1 /* POSIX compliant source */
#define FALSE 0
#define TRUE 1
volatile int STOP=FALSE;
volatile int wait_flag = FALSE;
void signal_handler_IO (int status);
#include <termios.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/signal.h>
#include <sys/types.h>
#include <iostream>
using namespace std;
int main(void)
{
int fd,c, res;
struct termios oldtio,newtio;
struct sigaction saio; /* definition of signal action */
char buf[255];
fd = open(MODEMDEVICE, O_RDWR | O_NOCTTY |O_NDELAY);
if (fd <0) {perror(MODEMDEVICE); exit(-1); }
/* install the signal handler before making the device asynchronous */
__sigset_t t;
saio.sa_handler = signal_handler_IO;
saio.sa_mask = t;
saio.sa_flags = 0;
saio.sa_restorer = NULL;
sigaction(SIGIO,&saio,NULL);
/* allow the process to receive SIGIO */
fcntl(fd, F_SETOWN, getpid());
/* Make the file descriptor asynchronous (the manual page says only
O_APPEND and O_NONBLOCK, will work with F_SETFL...) */
fcntl(fd, F_SETFL, FASYNC);
tcgetattr(fd,&oldtio); /* save current port settings */
bzero(&newtio, sizeof(newtio));
newtio.c_cflag = BAUDRATE | CRTSCTS | CS8 | CLOCAL | CREAD;
newtio.c_iflag = IGNPAR;
newtio.c_oflag = 0;
/* set input mode (non-canonical, no echo,...) */
newtio.c_lflag = 0;
newtio.c_cc[VTIME] = 0; /* inter-character timer unused */
newtio.c_cc[VMIN] = 0; /* blocking read until 5 chars received */
tcflush(fd, TCIFLUSH);
tcsetattr(fd,TCSANOW,&newtio);
while (STOP==FALSE) { /* loop for input */
printf(".\n");usleep(100000);
if(!wait_flag)
{
res = read(fd,buf,255); /* returns after 5 chars have been input */
buf[res]=0;
printf(":%s:%d\n", buf, res);
wait_flag = TRUE;
}
res = write(fd,"recu",4); /* returns after 5 chars have been input */
printf("emit: %d",res);
/* so we can printf... */
if (buf[0]=='z') STOP=TRUE;
}
tcsetattr(fd,TCSANOW,&oldtio);
exit(0);
}
/***************************************************************************
* signal handler. sets wait_flag to FALSE, to indicate above loop that *
* characters have been received. *
***************************************************************************/
void signal_handler_IO (int status)
{
printf("received SIGIO signal.\n");
wait_flag = FALSE;
} |
