...memory.
With the file caching available on modern operating systems, this distinction is actually rather blurred.
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...input
Strictly speaking, NDF_FORMATS_IN defines the formats recognised when accessing pre-existing datasets. Although it is possible to update and write to such datasets, it is nevertheless convenient to refer to them as ``input'' datasets.
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...system.
On UNIX, this will be the ``sh'' (Bourne) shell.
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...occur).
But also see §[*] for ways of avoiding this restriction.
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...output
As before, we really mean new datasets here (because you could write output to a pre-existing dataset, which is covered by the NDF_FORMATS_IN list), but thinking of them as ``output'' datasets is more convenient.
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...given.
Note that in this case the input format description is being used to create the output dataset, so it would not strictly be necessary for the FIGARO format to appear in the NDF_FORMATS_OUT list.
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...
Be careful to distinguish an ``extension'' to an NDF data structure (which is an addition of extra data to the file) from the ``file extension'' (which is the end part of the file name, such as `.sdf', used to identify the file's format).
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...
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...HREF="http://www.gsfc.nasa.gov/astro/fits/fits_home.html">FITS
FITS stands for Flexible Image Transport System.
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Starlink System Note 20
R.F.Warren-Smith & D.S.Berry
17th July 2000
E-mail:ussc@star.rl.ac.uk

Copyright © 2000 Council for the Central Laboratory of the Research Councils