The term “calling an S procedure in the foreground” means that the procedure is executed under the control of the task in which the procedure call command is issued: no new task is created. Such procedures are also referred to as synchronously called procedures, or as “interactive procedures”, because interactions with the user are possible if the procedure is called in dialog. Procedure calls in the foreground can be issued both from the system level and from within a procedure. S procedures are called in the foreground by a CALL-PROCEDURE command or by an INCLUDE-PROCEDURE command.
Procedures that are called by a CALL-PROCEDURE command are also referred to as call procedures; in the same way, procedures called by an INCLUDE-PROCEDURE command are referred to as include procedures.
Note
CALL-PROCEDURE can be used both to call S procedures in non-S procedures and to call non-S procedures in S procedures.