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

Charlie,

This is fixed in tonight's snapshot and fix will be in upcoming release.

--Russ

> > I am using rc1, not a snapshot, so far as I know:
> >
> > zender@roulee:~/nco$ ncks --lib
> > Linked to netCDF library version 4.2.1-rc1, compiled Jun 21 2012 22:52:46
> >
> > zender@roulee:~/nco$ nc-config --version
> > netCDF 4.2.1-rc1
> >
> > Puzzling. What is your UMASK value?
> 
> It's 0002, but I think I see the problem.  In my testing, I was writing to
> a file that already existed, named "tmp.nc" that had 644 permissions, so
> nccopy wasn't changing the permissions, although it was overwriting the
> file.  Apparently the bug is still there for creating a new file, it looks
> like it ignores the umask value in that case:
> 
> $ umask
> 0002
> $ nccopy test1.nc tmp.nc && ls -l tmp.nc
> -rw-rw-r-- 1 russ ustaff 108 Jun 27 13:41 tmp.nc
> $ nccopy -w test0.nc tmp.nc && ls -l tmp.nc
> -rw-rw-r-- 1 russ ustaff 104 Jun 27 13:41 tmp.nc
> $ rm tmp.nc
> $ nccopy -w test0.nc tmp.nc && ls -l tmp.nc
> -rwxrwxr-x 1 russ ustaff 104 Jun 27 13:42 tmp.nc
> 
> Thanks for reporting this!  We'll try to fix it for real, this time ...
> 
> --Russ
> 
> > On 06/27/2012 11:47 AM, Unidata netCDF Support wrote:
> > > 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
> > >
> > >
> >
> >
> > --
> > Charlie Zender, Department of Earth System Science
> > University of California, Irvine 949-891-2429  )'(
> >
> >
> 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