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AST_CURRENTTIME
-
Return the current system time
- Description:
- This routine
returns the current system time, represented in the form specified
by the supplied TimeFrame. That is, the returned floating point
value should be interpreted using the attribute values of the
TimeFrame. This includes System, TimeOrigin, LTOffset, TimeScale,
and Unit.
- Invocation:
- RESULT = AST_CURRENTTIME( THIS, STATUS )
- Arguments:
-
THIS = INTEGER (Given)
-
Pointer to the TimeFrame.
-
STATUS = INTEGER (Given and Returned)
-
The global status.
- Returned Value:
-
AST_CURRENTTIME = DOUBLE
-
- Notes:
- Values of AST__BAD will be returned if this function is
invoked with STATUS set to an error value, or if it should fail for
any reason.
- It is assumes that the system time (returned by the C time()
function) follows the POSIX standard, representing a continuous
monotonic increasing count of SI seconds since the epoch 00:00:00
UTC 1 January 1970 AD (equivalent to TAI with a constant offset).
Resolution is one second.
- An error will be reported if the TimeFrame has a TimeScale value
which cannot be converted to TAI (e.g. "angular" systems such as
UT1, GMST, LMST and LAST).
- Any inaccuracy in the system clock will be reflected in the value
returned by this function.
Next: AST_CURVE - Draw a geodesic curve
Up: AST Routine Descriptions
Previous: AST_COPY - Copy an Object
AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk
Copyright (C) 2009 Science \& Technology Facilities Council