Can't use q to quit in oneshot mode

[ghost]

If you launch zbarcam with -1 or --oneshot, , q to quit no longer works.

[matheusmoreira]

That's true. Here's the code I wrote that handles one shot mode:

zbar/zbarcam/zbarcam.c

Lines 327 to 365 in 150df8e

	/* start video */
	active = 1;
	if (zbar_processor_set_active(proc, active))
	return (zbar_processor_error_spew(proc, 0));
	if (oneshot) {
	if (zbar_process_one(proc, -1) < 0)
	if (zbar_processor_get_error_code(proc) != ZBAR_ERR_CLOSED)
	return zbar_processor_error_spew(proc, 0);
	} else {
	/* let the callback handle data */
	int rc;
	while ((rc = zbar_processor_user_wait(proc, -1)) >= 0) {
	if (rc == 'q' || rc == 'Q')
	break;
	// HACK: controls are known on V4L2 by ID, not by name. This is also
	// not compatible with other platforms
	if (rc == 'b' || rc == 'B') {
	int value;
	zbar_processor_get_control(proc, "Brightness", &value);
	zbar_processor_set_control(proc, "Brightness", ++value);
	}
	if (rc == 'n' || rc == 'N') {
	int value;
	zbar_processor_get_control(proc, "Brightness", &value);
	zbar_processor_set_control(proc, "Brightness", --value);
	}
	if (rc == ' ') {
	active = !active;
	if (zbar_processor_set_active(proc, active))
	return (zbar_processor_error_spew(proc, 0));
	}
	}
	/* report any errors that aren't "window closed" */
	if (rc && rc != 'q' && rc != 'Q' &&
	zbar_processor_get_error_code(proc) != ZBAR_ERR_CLOSED)
	return (zbar_processor_error_spew(proc, 0));
	}

In order to support camera controls, that if (oneshot) statement must be moved into the while loop somehow. I couldn't figure out a way to do it back then. I simply used the zbar_process_one interface:

zbar/include/zbar.h

Lines 955 to 967 in 150df8e

	/** process from the video stream until a result is available,
	* or the timeout (in milliseconds) expires.
	* specify a timeout of -1 to scan indefinitely
	* (zbar_processor_set_active() may still be used to abort the scan
	* from another thread).
	* if the library window is visible, video display will be enabled.
	* @note that multiple results may still be returned (despite the
	* name).
	* @returns >0 if symbols were successfully decoded,
	* 0 if no symbols were found (ie, the timeout expired)
	* or -1 if an error occurs
	*/
	extern int zbar_process_one(zbar_processor_t *processor, int timeout);

... Which ironically does not return exactly one result, it turns out.