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[ldm-users] 6.6.0 GEMPAK's dcncprof not removing ~/.tmp_netcdf. files from LDM's home

Good morning all,
Over the years, I have noticed various shell operations on my LDM system slow down. I just sort of assumed it was getting old like me! This morning I decided to resolve why ldm user shell logins were taking 10-20 seconds to happen.
After debugging the login, I discovered thousands of .tmp_netcdf.* files in the ldm user's home directory. I asked my friend Google what it thought of this and ran into this thread: 

https://www.unidata.ucar.edu/support/help/MailArchives/ldm-mcidas/msg00489.html
Which pointed a finger at GEMPAK's dcncprof, but the thread appeared to go silent. My LDM system runs GEMPAK 6.6.0, so I diffed the difference in dcncprof.c between that version and 7.0.4 

181c181
<       tempnam = (char *)malloc(32);
---

      tempnam = (char *)malloc(19);

183,184c183,184
<       sprintf(tempnam,".tmp_dcncprof_netcdf.XXXXXX\0");
<       mktemp(tempnam);
---

      sprintf(tempnam,".tmp_netcdf.XXXXXX\0");
      mkstemp(tempnam);

192c192
<          outfilnam = (char *)malloc(strlen(ofil)+33);
---

         outfilnam = (char *)malloc(strlen(ofil)+20);

216d215
<    close(outfilnam);
So the differences are mktemp vs mkstemp and that's the bug. mkstemp returns an open file descriptor that is never closed nor deleted. strace shows the fun too: 

open(".tmp_netcdf.Bm67hk", O_RDWR|O_CREAT|O_EXCL, 0600) = 4
open("/data/gempak/profiler/.tmp_netcdf.Bm67hk", O_WRONLY|O_CREAT|O_TRUNC, 0644) = 5
So moral of the story, look for lots of .tmp_netcdf.* files in your LDM's home directory and upgrade GEMPAK :) 

PS: This command may be useful to you if you have so many files that

    rm .tmp_netcdf.*

fails.

    find . -name '.tmp_netcdf.*' -exec rm {} \

daryl

--
/**
 * Daryl Herzmann
 * Assistant Scientist -- Iowa Environmental Mesonet
 * http://mesonet.agron.iastate.edu
 */
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