What is the usage of EXTERNAL_CLIENT_LIBRARY and EXTERNAL_CLIENT_DIRECTORY?

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Hi, Experts:
I wonder the usage of EXTERNAL_CLIENT_LIBRARY and EXTERNAL_CLIENT_DIRECTORY:

  1. If the real env variable name for EXTERNAL_CLIENT_LIBRARY is FDB_NETWORK_OPTION_EXTERNAL_CLIENT_DIRECTORY? And FDB_NETWORK_OPTION_EXTERNAL_CLIENT_LIBRARY for EXTERNAL_CLIENT_LIBRARY?
  2. If the 2 parameters should be set concurrently?
  3. FDB_NETWORK_OPTION_EXTERNAL_CLIENT_DIRECTORY is for binary files? Such as fdbserver,fdbmonitor,fdbcli… , right? FDB_NETWORK_OPTION_EXTERNAL_CLIENT_LIBRARY is for lib files, such as libfdb_c.so ?
  4. Is there any example for the 2 parameters usage?
    Thanks!
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Both options are used to add client libraries (libfdb_c.so, or the similar file corresponding to your platform) to be used as external libraries.

EXTERNAL_CLIENT_LIBRARY lets you specify the path to a single library directly, while EXTERNAL_CLIENT_DIRECTORY lets you specify a directory from which all .so files are attempted to be used. It’s usually not necessary to use both, but if your setup required it you certainly could (e.g. if you had one directory of fdb_c libraries and one other fdb_c to load from another location).

EXTERNAL_CLIENT_LIBRARY is the name of the network option that you can set programmatically, but if you want to set it via environment variable the correct prefix is FDB_NETWORK_OPTION_ (see setting network options with environment variables).

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@ajbeamon Thank you for your explaination!