[Xastir] GNIS data

[Curt, WE7U]

On Thu, 26 May 2005, Wes Johnston wrote:

> I'm working with the local NWS office.... he wanted city names, so I
> told him how to create the linked folder z under the maps folder, and
> that works.  I send him a file called 0pop_places_over_500.gnis at first
> , and that displays the cities.  But he wanted more details, so I sent
> him a file called GASC.gnis that contains only towns in GA and SC... but
> it's got all of them.  Problem is, that xastir keeps displaying the city
> names from 0pop_places_over_500.gnis  even though he's deleted the
> file.  And it never shows towns from the GASC.gnis file even though it's
> shown and selected in the map chooser.  He's running cygwin xasir that
> we compiled about a month ago for him.
>
> How do we purge the 0pop_places file contents, and how do we make it
> display the GASC file?  Funny thing is, it's working fine for me on my
> cygwin/xastir work PC.

The way Unix/Linux works:  If you have any directory entry pointing
to a file, the file won't get deleted.  Basically if you have 3 hard
links to a file and delete two of them, the file will still be on
disk and you can get to it with that third directory entry.

Symbolic links don't do this though, only hard links which are the
same as the initial directory entry for the file.

Also:  If a program has a file open and you open a shell and delete
the file, the file will still be on disk and the program will be
able to manipulate the file.  As soon as the file is closed by the
program though it will be deleted.  This is a good trick for
creating temporary files that other programs can't mess with BTW.

To get back to the original problem though, it's possible that they
deleted a symlink from the GNIS directory, but the file itself is
still in the /usr/local/share/xastir/maps directory somewhere and
the Map Chooser still has it selected.  You can either bring up Map
Chooser and deselect the file, or you can close Xastir, delete the
~/.xastir/config/selected_maps.sys file, and restart Xastir.  That
last bit will deselect all maps.  You can also start Xastir like
this:  "xastir -m &"   which will deselect all maps.

--
Curt, WE7U.   APRS Client Comparisons: http://www.eskimo.com/~archer
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