Depending on the system you are testing, you may need to synchronize the input that a Vuser sends to a terminal emulator with the subsequent responses from the server. When you synchronize input, you instruct the Vuser to suspend script execution and wait for a cue from the system, before the Vuser performs its next action. For instance, suppose that a human user wants to submit the following sequence of key strokes to a bank application:
In this example, the input to the bank application is synchronized because at each step, the human user waits for a visual cue before typing.
This cue can be either the appearance of a particular message on the screen, or stability of all the information on the screen.
You can synchronize the input of a Vuser in the same way by using the TE-synchronization functions, TE_wait_sync, TE_wait_text, TE_wait_silent, and TE_wait_cursor. These functions effectively emulate a human user who types into a terminal window and then waits for the server to respond, before typing in the next command.
The TE_wait_sync function is used to synchronize block-mode (IBM) terminals only. The other TE-synchronization functions are used to synchronize character-mode (VT) terminals.
When you record an RTE Vuser script, VuGen can automatically generate and insert TE_wait_sync, TE_wait_text, and TE_wait_cursor statements into the script. You use VuGen's recording options to specify which synchronization functions VuGen should insert.
Note: Do not include any synchronization statements in the Vuser_end section of a Vuser script. Since a Vuser can be aborted at any time, you cannot predict when the Vuser_end section will be executed.