WAIT UNTIL

Syntax

WAIT UNTIL log_exp [UP TO sec SECONDS].

Addition:

Effect

This variant of the statement WAIT is designed

only for use by an asynchronous RFC with callback routines. It interrupts program execution for as long as the result of the logical expression log_exp is incorrect. For log_exp, an arbitrary logical expression can be specified.

If the result of log_exp is incorrect, the program waits until a callback routine of a previous function that was called asynchronously was executed and then checks the logical expression again. If the result of the logical expression is true or the callback routines of all functions called asynchronously beforehand have been executed, program execution is continued with the following statement in WAIT:

Addition

... UP TO sec SECONDS

Effect

With the specification UP TO, program interruption is limited maximum to the seconds specified in sec. For sec, a data object of type f is expected that must contain the positive number. At the end of the specified time, by the latest, program execution is continued with the following statement in WAIT:

System Fields

sy-subrc	Meaning
0	The logical condition log_exp was fulfilled.
4	No asynchronous function calls exist.
8	With specification of the addition UP TO, the maximum time was exceeded.

Notes

The statement WAIT causes a change in the work process, which is linked to rolling out and rolling in all loaded programs. For this reason, the time in sec should not be less than a second in order not to load the system with too frequent changing of the work process.
Each time the statement WAIT is used, a database commit is issued. For this reason, WAIT must not be used between Open SQL statements that open or close a database cursor.
There is also a variant of the statement WAIT that can be used independently of the asynchronous RFC.

Exceptions

Non-Catchable Exceptions

Cause: Undefined status of the WAIT statement.
Runtime Error: WAIT_ILLEGAL_CONTROL_BLOCK
Cause: Negative time specification for sec.
Runtime Error: WAIT_ILLEGAL_TIME_LIMIT