Add count of active fibers

src/inc/fiber.plh

@@ -1,4 +1,5 @@
 import fiber
     predef fbrInit(numPool), fbrStop(fid)#0, fbrExit#0, fbrStart(defaddr, param)
     predef fbrYield#0, fbrHalt#0, fbrResume(fid)#0
+    byte fbrCount
 end

src/libsrc/fiber.pla

@@ -19,6 +19,7 @@ byte fbrNext[MAX_FIBERS]
 word fbrVMState[MAX_FIBERS]
 word fbrPool
 byte fbrRunning = 0
+export byte fbrCount = 0
 //
 // Zero Page VM state and 6502 stack
 //
@@ -136,6 +137,7 @@ export def fbrInit(numPool)
     else
         return -1
     fin
+    fbrCount = 1
     return 0
 end
 //
@@ -151,6 +153,7 @@ export def fbrStop(fid)#0
         //
         // Remove fiber from RUN list and tag as free
         //
+        fbrCount--
         fbrState[fid] = FIBER_FREE
         i = 0
         while fbrNext[i] <> fid
@@ -212,6 +215,7 @@ export def fbrStart(defaddr, param)
             //
             // Return fiber ID (index)
             //
+            fbrCount++
             return i
         fin
     next

src/samplesrc/fibertest.pla

@@ -19,6 +19,5 @@ fbrInit(4)
 fbrStart(@fbrTest, 3)
 fbrStart(@fbrTest, 2)
 fbrStart(@fbrTest, 1)
-fbrYield; fbrYield; fbrYield; fbrYield
-
+while fbrCount > 1; fbrYield; loop
 done