PRB: Visual FoxPro In-Process Servers Do Not Run Concurrently

MORE INFORMATION

In order to preserve data integrity of variables, Microsoft Visual FoxPro blocks entry into the run-time while another object is in execution.

Steps to Reproduce Behavior

1. Create a Visual FoxPro COM .dll, called VFPMTS, by adding a program file with the following code to a project:

         DEFINE CLASS MTSServer as Custom OLEPUBLIC
   
         oAPPServer = .NULL.
         oObjectContext = .NULL.
         cErrorMsg = ""
   
         FUNCTION FastHit
            RETURN "Done. " + TIME()
         ENDFUNC
         FUNCTION SlowHit
         LPARAMETER lnSecs
            lnSecs=IIF(type("lnSecs")="N",lnSecs,5)
   
            THIS.oAppServer = CREATEOBJECT("MTXaS.Appserver.1")
            THIS.oObjectContext = THIS.oAppServer.GetObjectContext()
   
            lcOutput = ""
   
            FOR x = 1 to lnSecs * 300000
               i=1
            ENDFOR
   
            THIS.oObjectContext.SetComplete()
            RETURN lcOutput + "Done waiting for "+STR(lnSecs)+" secs"
         ENDFUNC
         FUNCTION Error
         LPARAMETER lnErrorNo, lcCode, lnLine
   
            THIS.cErrorMsg = THIS.cErrorMsg + STR(lnErrorNo)+ " - " ;
            + STR(lnLine) + " " + lcCode + " - " +Message()
         ENDFUNC
         ENDDEFINE
   						

2. Build the project into a multi-use COM .dll then add it to Microsoft Transaction Server (MTS) using the Import Component option of an MTS package.
3. Start up two Visual FoxPro sessions.

In Session one, run the following code from the Command window:

   o=create("vfpmts.mtsserver")
   ? o.SlowHit(35)
				

In Session two run the following code from the Command window:

   o=create("vfpmts.mtsserver")
   ? o.FastHit()
				

Make sure you run the call to FastHit after SlowHit starts.

Notice that the FastHit does not start until after the SlowHit completes.