1986 BMW 535 Clutch cylinders

I had very little clutch pedal for some time but it shifted well enough. Then on a cold day I did not have enough clutch pedal to put it in gear. I then tried to bleed the system thinking the hydrudlics might have taken on air. It pumped twice sending out fluid and then all presure was lost. There is plenty of brake fluid throughout all this. Would this indicate that the master clutch cylindar or the slave or both are gone? I've taken the slave off and held on to the shaft. There is a litte. Very little sound and movement with the clutch is depressed. So what's your best guess?