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>From: Edward Hindman <address@hidden> >Organization: CCNY >Keywords: 200009220055.e8M0teb08133 McIDAS-X IMGPROBE OD Ward, >I am using McIDAS in my oceanography class to measure real-time >sea-surface temperatures using the ALT-D command and the OD L T. It turns out that there were a few things messed up on halo. Please read on. First, I want to remind you that the OD command only works with images loaded with the non-ADDE command DF (and programs that run DF like ALOOP). If you load an image with IMGDISP, OD can not be used; you have to use IMGPROBE or ALT-D. Images loaded from the Unidata McIDAS-X 7.6x Fkey menu are loaded with IMGDISPs; images loaded from the Unidata McIDAS-X 7.6 MCGUI are loaded with ALOOP which runs DF. So, you should expect the images loaded from the Fkey menu and from the command line with IMGDISPs to be interrogatable by IMGPROBE (ALT-D just runs IMGPROBE). Images loaded from the MCGUI or from DF commands can be interrogated by OD. >The ALT-D command sometimes works and sometimes does not work. I believe that I found the reason for this. It looks like there have been a number of aborted McIDAS-X sessions run as the user 'wxnut'. This did the following: o leave a lot of shared memory segments allocated, but not used. This was taking up system resources so that other processes couldn't use them. o one or more of the 'wxnut' McIDAS-X sessions that had failed had dumped files in the /home/mcidas/help directory. The files that had been dumped were ones that should be located in subdirectories of ~wxnut/.mctmp. These files are meant to be transitory: they should go away when a session is EXITed. The fact that the /home/mcidas/help directory is in every McIDAS-X user's MCPATH means that those copies of the dumped files (named FrameN.M, where N and M are numbers) will be used in everyone's sessions. The BIG problem with this are that simulatenous sessions will conflict with each other, and some users will not be able to write to the files, so McIDAS programs will start failing in mysterious ways. This is, in fact, what is causing the error you report next: >When it doesn't work we get the following error message: > >OD: AREA NOT PRESENT= >OD: Program called abort >IMGPROBE: Data service module problem, RC= -1 >IMGPROBE: Local interface module cannot be found >IMGPROBE: ival for mcadir= -98 >IMGPROBE: Failed to set up directory server This was being caused by orphaned copies of FrameN.M existing in /home/mcidas/data. After I forced the McIDAS-X session being run by 'wxnut' to EXIT, I was able to clean up these files, removed the orphaned shared memory setments, and get things working as they should. Things even seemed like they were running faster, but that could have been a result of the time (after 10 pm your time). >The OD L T command never works and we get the following diagnostic: > >OD: AREA NOT PRESENT= >OD: Program called abort This means that the images are never loaded with DF, ALOOP, so you have to use IMGPROBE. >I would appreciate it if you could logon to "Halo" and see if you can make >these two "bread and butter" commands work. I can't make OD work on ADDE loaded images. Also, it is being sunset, so it is best to use only IMGPROBE/ALT-D. I did login and found the orphaned file problem I mentioned above and the large number of shared memory segments owned by 'wxnut'. I removed those segments using the 'ipcrm' facility of Uhix. After cleaning up, I ran McIDAS-X sessions both as 'wxnut' and as 'mcidas' and was able to display images and interrogate them. Since I used the Fkey menu to load the images, I used IMGPROBE to probe them. All of the IMGPROBEs and ALT-Ds that I tried worked as expected. Give the cleaned up setup a go tomorrow and let me know if things don't work as you hope. Remember, however, that you will not be able to use OD on images loaded from the Fkey menu. You will need to use IMGPROBE exclusively (and ALT-D which runs IMGPROBE). >Ward Hindman >CCNY Tom