Contents - Index


Internet Update

WXtrack has the ability to update your Keplers over the Internet ready for the next run of the program.  WXtrack will never call up the Internet without asking your permission.  The list of files to update is obtained from the path you specified on the Setup tab.  There are four components to the Internet Update dialog box:
  • a check list box of files to update.
  • an Edit box with the base URL from which the files will be obtained.  Either HTTP or FTP can be used.
  • an optional command that can be run after an update (e.g. batch file to copy new Keplers).
  • an Update button to start the update.

    Once the update has started, the name of the file being updated and a progress box reflecting the progress through the list of files will be visible.  If you do not wish to update, press the Cancel button.  You can alter the base URL should you wish, and your changes will be saved between runs of WXtrack.

    Alternatively, you can reload the Keplers from file by pressing the Reload Only button, if you have an alterntive way of keeping the files up to date.

    The new Keplers will be used without restarting WXtrack.  A brief report will be displayed after both successful updates, and if any files are missing from the Web server (i.e files you may maintain yourself).

    Filenames during the update

    WXtrack can use the file extensions .2LI or .TLE for files containing the two-line orbital data.  However, on the Web site these files are named .txt.  The way that WXtrack handles this is to assume that every file in use named .2LI or .TLE has a corresponding .txt file on the server.  When the file is updated, the contents of the server's .txt file will replace the .2LI or .TLE file.

    Failed transfers

    There are two simple sanity checks on the files that have been brought back from the server.  The first is done by scanning down the file and ensuring that every second line (of three) starts "1 ", and every third line (of three) starts "2 ".  The second is to check that the  number of Keplers contained in each file differ by no more than 2.  If the transfer fails for some reason, these sanity checks will fail, and any recovered text from the server will displayed to help you determine what went wrong.  Data which fails these checks will not be written to your files.

    Required Support File - WinInet.dll

    Please note that this feature requires the library WinInet.dll.  This library is installed with Microsoft Internet Explorer and many other products.  However, if you do not have this library, you will need to update your Kepler elements files manually.  

    Proxy Limitations

    WXtrack cannot currently work with a proxy server that requires a username and password to authenticate the user.  Manual update is then required.