Open Watcom FORTRAN 77 Language Reference

Language Reference
2.39 ENTRY Statement
ENTRY name [( [d [, d] ...] )]
where:
name
d
is a symbolic name of an entry in a function or subroutine subprogram. If the ENTRY statement
appears in a subroutine subprogram then name is a subroutine name. If the ENTRY statement
appears in a function subprogram then name is an external function name.
is a variable name, array name, dummy procedure name, or an asterisk. d is called a dummy
argument. An asterisk is allowed only in a subroutine subprogram.
The ENTRY statement is used to define an alternate entry into a subprogram.
Example:
PRINT *, TMAX2( 121.0, -290.0 )
PRINT *, TMAX3( -1.0, 12.0, 5.0 )
END
FUNCTION TMAX3( ARGA, ARGB, ARGC )
T3 = ARGC
GO TO 10
ENTRY TMAX2( ARGA, ARGB )
T3 = ARGA
10 TMAX2 = ARGA
IF( ARGB .GT. TMAX2 ) TMAX2 = ARGB
IF( T3 .GT. TMAX2 ) TMAX2 = T3
END
In the above example, an entry was defined to permit us to find the maximum of two real variables. Either
the entry name TMAX2 or the function name TMAX3 could have been used as the variable for returning the
maximum value since they agree in type. It is not necessary to precede an ENTRY statement with a transfer
statement as the ENTRY statement is not an executable statement; the next statement executed will be the
first executable statement following the ENTRY statement.
Notes:
1. No dummy arguments need be specified in the ENTRY statement. If this is the case, the
parentheses () are optional.
For more information, see the chapter entitled "Functions and Subroutines" on page 243.
70 ENTRY Statement