HP 3000 Manuals HP 3000 Manuals
Data File Migration Data file migration is necessary only if real numbers exist in a data file. This section explains how to convert data files that contain real numbers previously used as input to Transact/V programs on MPE V systems for use with native mode Transact/iX programs running on MPE/iX systems. File Format Conversion The standard format for real numbers on MPE/iX-based systems is the IEEE format. This is different from the format for real numbers on MPE V-based systems. By default, for improved performance, native mode Transact/iX assumes that real numbers are in IEEE format. If you want to continue to use the MPE V format for real numbers, specify the HP3000_16 option in the INFO string when the native mode Transact/iX program is compiled. This option instructs the native mode Transact/iX compiler to read and write all real numbers in the MPE V format. If this option is used, no data file conversion is necessary. The MPE V-based data file can be restored onto the MPE/iX system and used without conversion. To migrate the data file to the MPE/iX standard format, you must write a native mode Transact/iX program that reads the file with the HP3000_16 option and writes the data to a new file with the HP3000_32 option. Native mode Transact/iX automatically converts the real numbers after reading them from the input file and before writing them to the output file. An example program is included in the next section.
CAUTION The internal representation of real numbers on MPE V is different from the IEEE format used on MPE/iX. This may cause individual values to change slightly during conversion. Compatibility mode Transact/iX programs cannot read IEEE format data. Do not migrate data files until all programs accessing those files have been converted to native mode Transact/iX.