20050804: saving files using pqact conf file

>From: Janet Scannell <address@hidden>
>Organization: UCAR
>Keywords: 200508041829.j74ITCjo002711 LDM pqact

Hi Janet,

>This is what I have in my ldmd.conf file:
>request EXP ".*\.png" malbec.atd.ucar.edu

This can better be expressed as:

request EXP "\.png" malbec.atd.ucar.edu

The leading ".*" is not needed and causes the regular expression
parser to work a lot harder than the simplified pattern.  If
you are doing a lot of processing, this will show up as excessive
CPU use.

>This is what I have in my pqact.conf file:
>EXP     ^(.*)   FILE    -close  /jnet/http/htdocs/composite/\1

>EXP     ^(.*)   FILE    -overwrite|-close       
>/jnet/http/htdocs/composite/current.png

This action should be rewritten as:

EXP     .*
        FILE    -close  -overwrite
        /jnet/http/htdocs/composite/current.png

The important part of this modification is the elimination of the
'|' between -overwrite and -close, not the multiple lines.

>I want to save the images coming into the ldm as the name that the file 
>came over as and also as current.png name in the specified directory.  

OK.

>This way when the images are sent to the plane, the current image is 
>always the same name and can be viewed through the web browser.  The 
>latest image is always displayed in the web browser because of the 
>refresh that I'm using.  I'm noticing that I often get a file length of 
>0 in current.png file.  Is there a way to fix this so that I don't get a 
>0 length file?

If a non-zero length product is received, a non-zero length product
will be written.  If zero-length products are possible and you
want to eliminate the processing of them, I recommend writing a
simple shell script that will be executed by the pqact.conf entry.
The script should read from STDIN and write to a scratch output
file.  If the scratch output file is non-zero length, write it to
the desired output file.

>The LDM doesn't appear to be sending images of 0 length 
>because there is no corresponding 0 length file of another name.

??

>The 
>LDM seems to create the 0 length current.png file when the LDM starts 
>up.  I'm not sure if it happens at other times or not.  Is there any way 
>that I can stop the LDM from writing a 0 length current.png file?

Try the shell script approach as I suggest above.

>Thanks,

No worries.

Tom Yoksas
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