This directory is supplied to match the default cache directory of gscdbd. If
you run gscdbd from the directory above this with its default cache setting you
will notice that directories containing .ech files start to accumulate here.
These files will serve as local alternates to accessing the CD-ROMs directly.
The file names are the GSC small region designation plus an .ech suffix. The
directory structure matches that of the CD-ROM.

A few samples are included. See the source file cacheio.c for details on the
format. The stars are in a portable packed binary format but the header is just
ASCII. Thus, you can fairly easily find approximately which part of the sky
each cache file represents just by reading the first line. A handy way to
do this on UNIX is to use "head -1 <filename>".

The header line consists of the following fields. Because the absolute value of
the declination is stored one must also know that southern region ids are 4663
and greater.

	Version number
	Region ID
	Number of stars
	Eastern RA, radians
	abs(Dec nearest 0), radians
	south (1 or 0)
	<newline>
