You can use the Digital Distributed Time Service (DECdts)
    programming routines to obtain timestamps that are based on
    Coordinated Universal Time (UTC). You can also use the DECdts
    routines to translate among different timestamp formats and
    perform calculations on timestamps. Applications can use the
    timestamps that DECdts supplies to determine event sequencing,
    duration, and scheduling. Applications can call the DECdts
    routines from DECdts server or clerk systems.

    The Digital Distributed Time Service routines are written in
    the C programming language. You should be familiar with the
    basic DECdts concepts before you attempt to use the applications
    programming interface (API).

    The DECdts API routines can perform the following basic
    functions:

    o  Retrieve timestamp information

    o  Convert between binary timestamps that use different time
       structures

    o  Convert between binary timestamps and ASCII representations

    o  Convert between UTC time and local time

    o  Convert the binary time values in the OpenVMS (Smithsonian-
       based) format to or from UTC-based binary timestamps (OpenVMS
       systems only)

    o  Manipulate binary timestamps

    o  Compare two binary time values

    o  Calculate binary time values

    o  Obtain time zone information

    DECdts can convert between several types of binary time
    structures that are based on different calendars and time unit
    measurements. DECdts uses UTC-based time structures and can
    convert other types of time structures to its own presentation
    of UTC-based time.