Test Script Services Reference

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Synchronization Class


Use the synchronization methods to synchronize virtual testers during script playback. You can insert synchronization points and wait periods, and you can manage variables shared among virtual testers.


Applicability

Commonly used with TestManager.


Summary

The following table lists the synchronization methods. They are methods of class TSSSync.

Method Description
SharedVarAssign Performs a shared variable assignment operation.
SharedVarEval Gets the value of a shared variable and operates on the value as specified.
SharedVarWait Waits for the value of a shared variable to match a specified range.
SyncPoint Puts a synchronization point in a script.


TSSSync.SharedVarAssign

Performs a shared variable assignment operation.


Syntax

SharedVarAssign (name As String, value As Long, [op As Long]) As 
Long

Element Description
name The name of the shared variable to operate on.
value The right-side value of the assignment expression.
op Assignment operator. Can be one of the following:
  • SHVOP_assign (default)

  • SHVOP_add

  • SHVOP_subtract

  • SHVOP_multliply

  • SHVOP_divide

  • SHVOP_modulo

  • SHVOP_and

  • SHVOP_or

  • SHVOP_xor

  • SHVOP_shiftleft

  • SHVOP_shiftright


Error Codes

This method may generate one of the followingerror codes:

If you handle one of these errors and do not log it, TestManager is not aware of the error and does not log a Fail result for it. The script continues to run, and TestManager could log a Pass result for the script.


Comments

Shared variables require configuration. For details, see Appendix A.


Example

This example adds 5 to the value of the shared variable lineCounter and puts the new value of lineCounter in returnval.

Dim returnVal as Long
Dim sync As New TSSSync
returnVal = sync.SharedVarAssign "lineCounter", 5, SHVOP_add

See Also

SharedVarEval, SharedVarWait


TSSSync.SharedVarEval

Gets the value of a shared variable and operates on the value as specified.


Syntax

SharedVarEval (name As String, value As Long, [op As Long]) As 
Long

Element Description
name The name of the shared variable to operate on.
value OUTPUT. A local container into which the value of name is retrieved.
op Increment/decrement operator for the returned value: Can be one of the following:
  • SHVADJ_none (default)

  • SHVADJ_pre_inc

  • SHVADJ_post_inc

  • SHVADJ_pre_dec

  • SHVADJ_post_dec


Error Codes

This method may generate one of the followingerror codes:

If you handle one of these errors and do not log it, TestManager is not aware of the error and does not log a Fail result for it. The script continues to run, and TestManager could log a Pass result for the script.


Comments

Shared variables require configuration. For details, see Appendix A.


Example

This example post-decrements the value of shared variable lineCounter and stores the result in val.

Dim val, retVal as Long
Dim sync As New TSSSync
retVal = sync.SharedVarEval "lineCounter", val, SHVADJ_post_inc

See Also

SharedVarAssign, SharedVarWait


TSSSync.SharedVarWait

Waits for the value of a shared variable to match a specified range.


Syntax

SharedVarWait (name As String, min As Long, [max As Long], 
[adjust As Long], [timeout As Long], [returnVal As Long]) As 
Long

Element Description
name The name of the shared variable to operate on.
min The low range for the value of name.
max The high range for the value of name.
adjust The value to increment/decrement the named shared variable by once it meets the min - max range.
timeout The time-out preference (how long to wait for the condition to be met). Enter one of the following:
  • A negative number for no time-out.

  • 0 to return immediately with an exit value of 1 (condition met) or 0 (not met).

  • The number of milliseconds to wait for the value of name to meet the criteria, before timing out with and returning an exit value of 1 (met) or 0 (not met).

returnVal OUTPUT. The value of name at the time of the return, before any possible adjustment. If timeout expired before the return, the value is not adjusted. Otherwise, returnVal is incremented/decremented by adjust.


Return Value

On success, this method returns 1 (condition was met before time-out) or 0 (time-out expired before the condition was met).


Error Codes

This method may generate one of the followingerror codes:

If you handle one of these errors and do not log it, TestManager is not aware of the error and does not log a Fail result for it. The script continues to run, and TestManager could log a Pass result for the script.


Comments

This call provides a method of blocking a virtual tester until a user-defined global event occurs.

If virtual testers are blocked on an event using the same shared variable, TestManager guarantees that the virtual testers are unblocked in the same order in which they were blocked.

Although this alone does not ensure an exact multiuser timing order in which statements following a wait are executed, the additional proper use of the arguments min, max, and adjust allows control over the order in which multiuser operations occur. (UNIX or Windows NT determines the order of the scheduling algorithms. For example, if two virtual testers are unblocked from a wait in a given order, the tester that was unblocked last might be released before the tester that was unblocked first.)

If a shared variable's value is modified, any subsequent attempt to modify this value -- other than through SharedVarWait -- blocks execution until all virtual testers already blocked have had an opportunity to unblock. This ensures that events cannot appear and then quickly disappear before a blocked virtual tester is unblocked. For example, if two virtual testers were blocked waiting for name to equal or exceed N, and if another virtual tester assigned the value N to name, then TestManager guarantees both virtual testers the opportunity to unblock before any other virtual tester is allowed to modify name.

Offering the opportunity for all virtual testers to unblock does not guarantee that all virtual testers actually unblock, because if SharedVarWait is called with a nonzero value of adjust by one or more of the blocked virtual testers, the shared variable value changes during the unblocking script. In the previous example, if the first user to unblock had called SharedVarWait with a negative adjust value, the event waited on by the second user would no longer be true after the first user unblocked. With proper choice of adjust values, you can control the order of events.

Shared variables require configuration. For details, see Appendix A.


Example

This example returns 1 if the shared variable inProgress reaches a value between 10 and 20 within 60000 milliseconds of the time of the call. Otherwise, it returns 0. svVal contains the value of inProgress at the time of the return, before it is adjusted. (In this case, the adjustment value is 0 so the value of the shared variable is not adjusted.)

Dim retVal, svVal As Long
svVal = 0
Dim sync As New TSSSync
retVal = sync.SharedVarWait "inProgress",10,20,0,60000,svVal

See Also

SharedVarAssign, SharedVarEval


TSSSync.SyncPoint

Puts a synchronization point in a script.


Syntax

SyncPoint (label As String)

Element Description
label The name of the synchronization point.


Error Codes

This method maygenerate one of the following error codes:

If you handle one of these errors and do not log it, TestManager is not aware of the error and does not log a Fail result for it. The script continues to run, and TestManager could log a Pass result for the script.


Comments

A script pauses at a synchronization point until the release criteria specified by the suite have been met. If the criteria are met, the script delays a random time specified in the suite and then resumes execution.

Typically, it is better to insert a synchronization point into a suite from TestManager rather than use the SyncPoint call inside a script.

If you insert a synchronization point into a suite, synchronization occurs at the beginning of the script. If you insert a synchronization point into a script with SyncPoint, synchronization occurs at the point of insertion. You can insert the command anywhere in the script.

Shared variables require configuration. For details, see Appendix A.


Example

This example creates a sync point named BlockUntilSaveComplete.

Dim sync As New TSSSync
sync.SyncPoint "BlockUntilSaveComplete"

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