gps time synchronization accuracy

i have a GPS NTP Time server s开发者_开发百科ynchronizing my PC. HOW am i able to compare 1PPS of the GPS receiver with clock pulse of my PC to see how much accurately it is synced to the GPS time?(with an oscilloscope maybe!)

I've designed experiments of this sort before. In my case, I wrote a device driver that would -- inside the kernel -- watch the PC's clock in a tight loop waiting for it to roll over to a new second. As soon as it did, I would raise one of the pins high on the PC parallel port. Then I attached that pin of the parallel port and the PPS signal output of the GPS receiver to an oscilloscope and had it measure the time difference between the two pulses.