cache
directory?
cache
directory with
unique names generated based on the process ID of the server program.
As each file is written, an at
job is queued to delete it
five minutes later. This way the image files are automatically cleaned up.
cgi-bin
(or whatever)
directory, others in your Web document server area, and then fix links all
over the place, both in the C code (since it creates HTML on the fly)
and in the documents. Then, of course, there's the CPU time that will
be eaten as folks start using your server. A 320╫320 pixel globe
image takes about 6 seconds of CPU time on the Sun SPARCStation 2
currently running the server.
nice
processes, with a priority level set depending on
the size of the image requested according to the formula:
nice = 6 + (size / 100)where size is the image size in pixels. Thus larger image requests are performed in the background with regard to smaller ones. The image rendering time goes as the square of the size. Since all requests are
nice
, if my machine is busy with regular
work, everything will slow down. This rarely happens, since the
machine on which the server is running is used almost exclusively as a
file server, not a crunch machine. Also, my network connection is
64 kbps, not one of those hulkin' T1 lines, and may become congested
if lots of requests arrive at once. Finally, if you're in the Western
Hemisphere or Asia, recall that it takes a while for the data to get
back and forth from your client to the server in Switzerland.
AAAAAAAAAAA 1 NNNNNU NNNNNAAA NNNNN.NNNNNNNN +.NNNNNNNN +NNNNN-N +NNNNN-N N NNNNN 2 NNNNN NNN.NNNN NNN.NNNN NNNNNNN NNN.NNNN NNN.NNNN NN.NNNNNNNNNNNNNNLine 0 is a eleven-character name.
Lines 1 and 2 are the standard Two-Line Orbital Element Set Format identical to that used by NORAD and NASA. The format description is:
Line 1 Column Description ------ --------------------------------------------------- 01-01 Line Number of Element Data 03-07 Satellite Number 10-11 International Designator (Last two digits of launch year) 12-14 International Designator (Launch number of the year) 15-17 International Designator (Piece of launch) 19-20 Epoch Year (Last two digits of year) 21-32 Epoch (Julian Day and fractional portion of the day) 34-43 First Time Derivative of the Mean Motion or Ballistic Coefficient (Depending on ephemeris type) 45-52 Second Time Derivative of Mean Motion (decimal point assumed; blank if N/A) 54-61 BSTAR drag term if GP4 general perturbation theory was used. Otherwise, radiation pressure coefficient. (Decimal point assumed) 63-63 Ephemeris type 65-68 Element number 69-69 Check Sum (Modulo 10) (Letters, blanks, periods = 0; minus sign = 1) Line 2 Column Description ------ --------------------------------------------------- 01-01 Line Number of Element Data 03-07 Satellite Number 09-16 Inclination [Degrees] 18-25 Right Ascension of the Ascending Node [Degrees] 27-33 Eccentricity (decimal point assumed) 35-42 Argument of Perigee [Degrees] 44-51 Mean Anomaly [Degrees] 53-63 Mean Motion [Revs per day] 64-68 Revolution number at epoch [Revs] 69-69 Check Sum (Modulo 10)All other columns are blank or fixed.
Example:
NOAA 6 1 11416U 86 50.28438588 0.00000140 67960-4 0 5293 2 11416 98.5105 69.3305 0012788 63.2828 296.9658 14.24899292346978