Incompatibilities – HP SunSoft Pascal 4.0 User Manual

Page 190

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166

Pascal 4.0 User’s Guide

8

Character Strings

There are some precautions to take with character strings regarding the null
byte, passing by value, and static storage:

Set the byte count to zero before calling Pascal with a null varying string,
because that is what Pascal assumes about such strings.

Pass a structure consisting of a 4-byte integer and an array of characters
from FORTRAN to a Pascal procedure, expecting a

var

parameter that is a

variable-length string.

Pass by reference by making the strings

var

,

in

,

out

, or

in out

parameters.

Set the string to constant because FORTRAN and Pascal each guarantees the
null byte only if the string is a constant. Neither of them relies on the null
byte, which is not required by the ISO Pascal Standard.

Array Indexes

The Pascal and FORTRAN array indexes can start at any integer; be sure they
match.

Incompatibilities

There are several incompatibilities between Pascal and FORTRAN variant
records, enumerated types, and set types.

Variant Records

In general, Pascal variant records require adjustment of alignment to match
with FORTRAN unions and structures.

Enumerated Types

Pascal enumerated types have no comparable type in FORTRAN.

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