DECLARE_CHARACTER

Declare a CHARACTER variable

Description:

Declare a CHARACTER variable that will be passed to a FORTRAN routine. This variable will be the actual argument of a call to a FORTRAN routine.

Invocation

DECLARE_CHARACTER(arg,length)

Arguments

arg
The variable being declared.
length
The length of the character string.

Examples:

DECLARE_CHARACTER(C,50)
will expand as follows:
All Unix: char C[50]; const int C_length = 50
VAX/VMS: char C[50]; const int C_length = 50;
struct dsc$descriptor_s C_descr =
{50, DSC$K_DTYPE_T, DSC$K_CLASS_S, C };
struct dsc$descriptor_s ∗C_arg =&C_descr

Notes:

On VMS, the expansion of the macro is quite complex. A char array is declared as well as an int variable to store the length of the array. There is also a descriptor and a pointer to that descriptor. The address of the descriptor is what is actually passed to the called FORTRAN routine.