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Entry  28 Jan 2024, Pavel Murat, Forum, number of entries in a given ODB subdirectory ? 
    Reply  28 Jan 2024, Konstantin Olchanski, Forum, number of entries in a given ODB subdirectory ? 
       Reply  28 Jan 2024, Stefan Ritt, Forum, number of entries in a given ODB subdirectory ? Screenshot_2024-01-29_at_07.20.50.png
          Reply  29 Jan 2024, Pavel Murat, Forum, number of entries in a given ODB subdirectory ? 
          Reply  29 Jan 2024, Konstantin Olchanski, Forum, number of entries in a given ODB subdirectory ? 
             Reply  03 Feb 2024, Pavel Murat, Forum, number of entries in a given ODB subdirectory ? a.cc
                Reply  08 Feb 2024, Stefan Ritt, Forum, number of entries in a given ODB subdirectory ? 
                   Reply  11 Feb 2024, Pavel Murat, Forum, number of entries in a given ODB subdirectory ? 
                      Reply  13 Feb 2024, Stefan Ritt, Forum, number of entries in a given ODB subdirectory ? 
                         Reply  15 Feb 2024, Konstantin Olchanski, Forum, number of entries in a given ODB subdirectory ? 
                            Reply  15 Feb 2024, Konstantin Olchanski, Forum, number of entries in a given ODB subdirectory ? 
                               Reply  15 Feb 2024, Stefan Ritt, Forum, number of entries in a given ODB subdirectory ? 
                                  Reply  19 Feb 2024, Pavel Murat, Forum, number of entries in a given ODB subdirectory ? 
Message ID: 2717     Entry time: 19 Feb 2024     In reply to: 2715
Author: Pavel Murat 
Topic: Forum 
Subject: number of entries in a given ODB subdirectory ? 
> > Hmm... is there any use case where you want to know the number of directory entries, but you will not iterate 
> > over them later?
> 
> I agree. 

here comes the use case: 

I have a slow control frontend which monitors several DAQ components - software processes. 
The components are listed in the system configuration stored in ODB, a subkey per component.

Each component has its own driver, so the length of the driver list, defined by the number of components, 
needs to be determined at run time.

I calculate the number of components by iterating over the list of component subkeys in the system configuration, 
allocate space for the driver list, and store the pointer to the driver list in the equipment record.

The approach works, but it does require pre-calculating the number of subkeys of a given key.

-- regards, Pasha
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