Communicator 3000 MPE/iX Release 6.0 (Platform Software Release C.60.00) (30216-90269)

Chapter 9 123

Year 2000 Enhancements

New Date Intrinsics for MPE/iX

by M Gopalakrishnan

Commercial Systems Division

This release of the MPE/iX operating system has enhanced intrinsics

for handling date formats. These intrinsics are targeted to support

widely used existing date formats in MPE/iX and three new date

formats.

The date intrinsics are broadly categorized as follows:

• HPDATECONVERT—Converting dates from one supported format to

another.

• HPDATEFORMAT—Converting the supported format dates to the

display formats desired by the user.

• HPDATEDIFF—Determining the number of days that separate two

given dates.

• HPDATEOFFSET—Adding/subtracting an offset (days) to/from the

given date.

• HPDATEVALIDATE—Validating the given date for conformance to a

supported date format.

• HPCALENDAR, HPFMTCALENDAR—Using the new 32-bit HPCALENDAR

format.

The following sections will discuss various date formats and the syntax

and semantics of new date intrinsics. COBOL and Pascal programs

using these intrinsics are provided as examples.

Existing Date Formats

Existing date formats that are widely used are summarized in the

following table, “Existing Date Formats.” The column “Sortable?”

indicates whether the dates can be sorted (either numerically or

lexicographically depending on how they are stored). The last column

“Y2K Ready?” indicates whether dates in the format under

consideration can be used to represent dates beyond 1999-12-31. The

column “#Bytes” represents the number of bytes required to store the

date format.