Non-blocking serial gets...

[Michael Richards]

I'm using the serial part of the library through a ttystream. I can't seem to find a way to get a character or determine if there is one waiting without my program blocking.

Here is a quick program to illustrate the problem:
#include "cc++/serial.h"
#include <iostream.h>

using namespace ost;

main() {
  ttystream modem("/dev/cuaa0");
  if (!modem) {
    cerr << "Unable to open modem\n";
    return 0;
  }

  modem.setSpeed(38400);
  modem.setCharBits(8);
  modem.setParity(Serial::parityNone);
  modem.setStopBits(1);
  modem.setFlowControl(Serial::flowHard);
  modem.toggleDTR(500);

  modem.interactive(true);
  modem << "ATZ\r";

  while (1) {
    cout << "Going to wait\n";
    char c=modem.get();
    cout << "Got a (" << c << ")\n";
  }
}

When run it outputs:
./test
Going to wait
Got a (A)
Going to wait
Got a (T)
Going to wait
Got a (Z)
Going to wait
)ot a (
Going to wait
)ot a (
Going to wait
Got a (
)
Going to wait
Got a (O)
Going to wait
Got a (K)
Going to wait
)ot a (
Going to wait
Got a (
)
Going to wait

This tells me that it's blocking on the get() call. How can I tell if there are chars waiting?

-Michael

[Buck]

shouldn't

        while (modem.isPending(pendingInput, suitableTimeout)) {
                cout << "not waiting for nobody!" << endl;
                char c;
                modem.get(c);
                cout << "got a (" << c << ")" << endl;
        }

do the trick?