Update a file if it is common for two directory and delete it when its uniquely in one directory

Question

Suppose Directory1 has

1.File1 
2.File2
3.Subdirectory1
    Subdirectory1 has :
    3.1. File 3
    3.2. File 4

and

Directory2 has

1.File1
2.File3
3.Subdirectory1
    Subdirectory1 has :
    3.1. File 3
    3.2. File 6

If any file is uniquely present in Directory2 it has to be deleted. If the file is present in both Directory1 and Directory2 , files in Directory1 has to be copied to Directory2 with the same folder structure [Updates].

Answer 1

Simply use diff, eg :

diff -r dir1 dir2 | grep dir1
Only in dir1: file2
Only in dir1/subdir1: file4
Only in dir2/subdir1: file6

You can then awk, or store the result in a temporary file and use it in your script.

Answer 2

You seem to talk about a mirroring function, see the nice Open Source tool rsync. https://rsync.samba.org/

It can do all of that and even more (also remote synchronization via LAN or via SSH if needed).

rsync -options --otherOptions sourceDir targetDir

Usually you would use these commandline options:

rsync -av /src/foo /dest
or
rsync -av /src/foo/ /dest/foo

Note: if you omit the trailing "/" of /src/foo, then rsync will mirror to /dest and create a foo subdir. You have either the one or the other choice how to use this command.