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[netCDF #MEJ-623272]: NC_DISKLESS file permissions question

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  • Subject: [netCDF #MEJ-623272]: NC_DISKLESS file permissions question
  • Date: Wed, 27 Jun 2012 12:47:01 -0600
Charlie,

I should have also pointed out that the fix takes UMASK into account,
rather than just setting the output file permissions to 644 ...

--Russ

> > What sets/controls the permissions on files nc_create()'d
> > with NC_DISKLESS? NCO normally creates files with UNIX
> > permissions 644 (octal), but those created with NC_DISKLESS have
> > mode 755. Wondering what the recommended way is to ensure
> > files are created with 644 permissions. I can invoke
> > chmod() from within NCO if necessary, though this seems
> > rather baroque.
> >
> > nccopy exhibits this behavior too, as shown here:
> >
> > zender@roulee:~$ nccopy -r -w ~/nco/data/in.nc ~/foo.nc
> > zender@roulee:~$ ls -l foo.nc
> > -rwxr-xr-x 1 zender zender 42356 Jun 26 23:36 foo.nc
> > zender@roulee:~$ nccopy -r ~/nco/data/in.nc ~/foo.nc
> > zender@roulee:~$ ls -l foo.nc
> > -rw-r--r-- 1 zender zender 42356 Jun 26 23:37 foo.nc
> 
> This problem is fixed in netcdf-4.2.1-rc1, announced last week.  Are
> you testing on a snapshot release from before that announcement?  I
> just tried it with 4.2.1-rc1 in nccopy, and the files it creates have
> 644 permissions.
> 
> Incidentally, I haven't found an example in using nccopy where the
> "-r" option for copying the input file into a diskless file first
> provides a performance improvement.
> 
> --Russ
> 
> Russ Rew                                         UCAR Unidata Program
> address@hidden                      http://www.unidata.ucar.edu
> 
> 

Russ Rew                                         UCAR Unidata Program
address@hidden                      http://www.unidata.ucar.edu



Ticket Details
===================
Ticket ID: MEJ-623272
Department: Support netCDF
Priority: Normal
Status: Closed