Additional Notes on Nonnative Data

The following notes apply to porting nonnative data:

• When porting source code along with the unformatted data, vendors might use different units for specifying the record length (RECL specifier) of unformatted files. While formatted files are specified in units of characters (bytes), unformatted files are specified in longword units for Compaq Fortran (default) and some other vendors.

  To allow you to specify the RECL units (bytes or longwords) for unformatted files without source file modification, use the /assume:byterecl compiler option (in the visual development environment, this is available in the Project menu Settings item, Fortran tab, Fortran Data category).

  The Fortran 90 standard (American National Standard Fortran 90, ANSI X3.198-1991, and International Standards Organization standard ISO/IEC 1539:1991), in Section 9.3.4.5, states: "If the file is being connected for unformatted input/output, the length is measured in processor-dependent units."

• Certain vendors apply different OPEN statement defaults to determine the record type. The default record type (RECORDTYPE) with Compaq Fortran depends on the values for the ACCESS and FORM specifiers for the OPEN statement (also described in the Compaq Fortran Language Reference Manual).
• Certain vendors use a different identifier for the logical data types, such as hex FF instead of 01 to denote "true."
• Source code being ported may be coded specifically for big endian use.