Inside Macintosh: Operating System Utilities /

Chapter 4 - Date, Time, and Measurement Utilities

This chapter describes a set of utility routines that you can use to operate on dates and times. You can use these routines to get and change information about the current date, time, geographic location, time zone, and units of measurement.

The routines described in this chapter return this information in a format that is best suited to the current script. As a result, you can facilitate localization of your application by using these date, time, and measurement utilities.

To understand the material in this chapter, you need to be familiar with the international resources, especially the numeric-format and long-date-format resources, and the Script Manager. These topics are described in Inside Macintosh: Text. In addition, the chapter "Text Utilities" in Inside Macintosh: Text describes how to convert date and time information into strings of text.

Many of the Date, Time, and Measurement Utilities were previously associated with other managers in the Macintosh system software, and several of these routines have been renamed. Table 4-4 on page 4-33 shows the original names and locations of the modified Date, Time, and Measurement Utilities routines.

The next section provides an introduction to the Date, Time, and Measurement Utilities.

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Chapter Contents

About the Date, Time, and Measurement Utilities

Date and Time

Geographic Location and Time Zone

System of Measurement

Time Measurement

Using the Date, Time, and Measurement Utilities

Getting the Current Date and Time

Setting the Current Date and Time

Converting Date-Time Formats

Calculating Dates

Working With Different Calendar Systems

Handling Geographic Location and Time-Zone Data

Determining the Measurement System

Determining the Number of Elapsed Microseconds

Date, Time, and Measurement Utilities Reference

Data Structures

The Date-Time Record

Long Date-Time Value and Long Date-Time Conversion Record

The Long Date-Time Record

The Geographic Location Record

The Toggle Parameter Block

The Unsigned Wide Record

Routines

Getting the Current Date and Time

Setting the Current Date and Time

Converting Between Date-Time Formats

Converting Between Long Date-Time Format

Modifying and Verifying Long Date-Time Records

Reading and Writing Location Data

Determining the Measurement System

Measuring Time

Summary of the Date, Time, and Measurement Utilities

Pascal Summary

Constants

Data Types

Routines

C Summary

Constants

Data Types

Routines

Assembly-Language Summary

Data Structures

Global Variables

Result Codes