The ENTRY statement provides one or more entry points within a subprogram. It is not executable and must precede any CONTAINS statement (if any) within the subprogram.
The ENTRY statement takes the following form:
Rules and Behavior
ENTRY statements can only appear in external procedures or module procedures.
An ENTRY statement must not appear in a CASE, DO, IF, FORALL, or WHERE construct, or a nonblock DO loop.
When the ENTRY statement appears in a subroutine subprogram, it is referenced by a CALL statement. When the ENTRY statement appears in a function subprogram, it is referenced by a function reference.
An entry name within a function subprogram can appear in a type declaration statement.
Within the subprogram containing the ENTRY statement, the entry name must not appear as a dummy argument in the FUNCTION or SUBROUTINE statement, and it must not appear in an EXTERNAL or INTRINSIC statement. For example, neither of the following are valid:
(1) SUBROUTINE SUB(E) ENTRY E ... (2) SUBROUTINE SUB EXTERNAL E ENTRY E ...
An ENTRY statement can reference itself if the function or subroutine subprogram was defined as RECURSIVE.
Dummy arguments can be used in ENTRY statements even if they differ in order, number, type and kind parameters, and name from the dummy arguments used in the FUNCTION, SUBROUTINE, and other ENTRY statements in the same subprogram. However, each reference to a function, subroutine, or entry must use an actual argument list that agrees in order, number, and type with the dummy argument list in the corresponding FUNCTION, SUBROUTINE, or ENTRY statement.
Dummy arguments can be referred to only in executable statements that follow the first SUBROUTINE, FUNCTION, or ENTRY statement in which the dummy argument is specified. If a dummy argument is not currently associated with an actual argument, the dummy argument is undefined and cannot be referenced. Arguments do not retain their association from one reference of a subprogram to another.
For specific information on ENTRY statements in function subprograms and subroutine subprograms (including examples), see Section 8.11.1 and Section 8.11.2, respectively.
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