Editing the names.gvar File

The names.gvar file is a configuration file that is used only with GVAR ingestors. It lists the GVAR descriptor file names and defines their sector boundaries (see the GVAR Descriptor Files description). Operators can edit this file to change descriptor boundaries if desired. Though most SDI GVAR ingestors have the same descriptors, each ingestor may define them differently via its names.gvar configuration file.

GVAR descriptors are used as search tools for locating GVAR images and their times for your geographical area of interest. For an image to be listed under a particular descriptor, it must include all of the sector area described by the descriptor's sector boundaries. This is a minimum requirement and some images may contain much more data than the descriptor indicates. For example, if you create a descriptor called WISC (Wisconsin) and set its sector boundaries just large enough to include all of the state of Wisconsin, WISC will contain any GVAR image that shows the entire state of Wisconsin. These images will include:

To change descriptor names or their boundaries, perform the following procedure.

1. From the console, login as root or ssh into the ingestor as root.

2. Edit the file /data/names.gvar.

The first line in the file must always be

ALL 0 0 0 0

The last line in file must always be

OTHER 1 0 0 0

The format of the file is: descriptor_name sline eline sele eele

Where:

descriptor_name	descriptor name (e.g., NH for Northern Hemisphere)
sline	starting image line number
eline	ending image line number
sele	starting image element
eele	ending image element

The table below is a sample GVAR descriptor file

Table 3-1: Sample Descriptor File Format (fields are space delimited)

ALL     0       0       0        0
CONUS   3250    5300    16700    17400
NH      3250    7400    11000    20000
SH      10200   10300   11000    12000
FD      2800    10000   11000    20000
OTHER   1       0       0        0

Example:

Using the names.gvar file above, any image that completely covers the area from image lines 3250 to 5300, and image elements 16700 to 17400 is listed in the descriptor file named CONUS.

3. Save the file.