How does SVN's Co exclude directories under Linux

Some reasons to exclude certain directories from SVN co can be done in three steps in a circle:

CO Outer directory:

SVN checkout--depth empty $URL [$LOCATION]

Once completed, there will be a root directory that contains only empty directories

Set Ignore directory:

CD $LOCATION
SVN up--set-depth exclude < $DIR _to_exclude>

So SVN prompts the ignored directory to mark D, and then the file system is invisible.

Update remaining files

SVN Up--set-depth Infinity *

This allows other directories to be recursively updated, the ignored directories are not updated, and the ignored files cannot be updated even after someone executes svn up.