user permissions
 

I am using ubuntu and im trying to figure out how to add a user and give it read and write access to one file on the entire server only. can anybody help me?

Hello

To add an user use add user (see man adduser for details)
Do you want the user to be able to log in ? You may don't want to create a home directory for it, so you may be interested in the --no-create-home option.
Then use chmod and chown to set the permissions. Something like (see man chown and man chmod for details) :
Note that you won't have only one file whith read write access for the user on the whole server, indeed there are world readable/writable files (wanting to give access to only one file on the whole server for an user seems odd to me)

Hope it helps.

Follow antegallya's instructions.

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