Detecting Carrier Status

ttumelty · 08-26-2005, 02:05 AM

To detect modem carrier status would this work :

#include <termios.h>
#include <unistd.h>

int fd;
int status;

int detectCarrier(void)
{
ioctl(fd, TIOCMGET, &status ); // get modem

status &= UART_MSR_DCD;

if ( status == 0 ) // carrier detected
res = TIOCM_CAR;
else if ( status != 0 ) // carrier not detected
res = 0;

return res;
}

randyding · 08-27-2005, 12:00 AM

I've always used a different macro, which may be the same, not sure.
ioctl(fd,TIOCMGET,&flags);
carrier_detected= 0!=(flags&TIOCM_CD);