DAQmx Counter Input Measure a single pulse's pulse width

Trying to measure a single pulse's pulse width. It appears that the DAQ only makes the measurement on the read command instead of after starting the task. I just get a timeout error. Is there any way to arm to counter for measurement or am I better off making a seperate thread to trigger my single pulse?

double measured;

int numSamp;

TaskHandle taskHandle;

DAQmxCreateTask("", &taskHandle);

DAQmxCreateCIPulseWidthChan(taskHandle, "Dev1/ctr0", "", 0.025, 0.120, DAQmx_Val_Seconds, DAQmx_Val_Rising, "");

DAQmxSetChanAttribute(taskHandle, "", DAQmx_CI_PulseWidth_Term, "/Dev1/PFI10");

DAQmxStartTask(taskHandle);

//Trigger the single pulse here

DAQmxReadCounterF64(taskHandle, DAQmx_Val_Auto, 10.0, &measured, 1, &numSamp, NULL);

Thanks,

Dan