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Jon, > My name is Jon Wolfe and I work for a wind-forecasting company. We use > LDM to download radar data and other data feeds, but none of us is > an expert with LDM. The issue we're seeing is that we have a chain > of commands in pqact we're trying to understand better. Basically, > as radar files come in we're trying to use a pipe command to convert > them and exec to run ready_radar: > > NEXRD2 > ^L2-([^/]*)/(....)/([0-9][0-9][0-9][0-9][0-1][0-9][0-3][0-9][0-2][0-9][0-5][0-9][0-9][0-9]) > PIPE -close nexradII /lustrefs/wind/data/radar/work/\2/\3 > > NEXRD2 > ^L2-([^/]*)/(....)/([0-9][0-9][0-9][0-9][0-1][0-9][0-3][0-9][0-2][0-9][0-5][0-9][0-9][0-9]) > EXEC bin/ready_radar.sh \2 \3 /lustrefs/wind/data/radar/work > /lustrefs/wind/data/radar/netCDF > > However, we're seeing our system get hammered in that ready_radar runs > over and over again as the files come in. So my question is, how can we > get the EXEC command to wait until the file has been completely downloaded > before running? The end result of all the hammering of the system has > been that some of the radar files don't ever come in completely and the > partial files cause us all kinds of problems. The two regular expressions look identical, so the associated actions will execute on the same data-products. This likely means that "ready_radar.sh" will be executed every time a radar product arrives -- regardless of whether or not the volume-scan to which it belongs is complete. I think the last product of a volume-scan has a "\E" suffix (you could check with notifyme(1)). If there's more than one path for radar products to get to your system, however, then that product can arrive before the volume-scan is complete. I'd be inclined to combine the "nexradII" and "ready_radar.sh" programs into a single script (whose first significant action would be to execute "nexradII"). The rest of the script would determine if the volume-scan is complete and execute the equivalent of "ready_radar.sh" if it was. I've BCC'ed our expert here on NEXRAD Level II processing in case they have something to add. > Thanks for your help, > > Jon Regards, Steve Emmerson Ticket Details =================== Ticket ID: VHO-548969 Department: Support LDM Priority: Normal Status: Closed