Question about File Permissions

[.AJ]

Hi,

The other day I was having a look around my Mac (relatively new Mac user) and found in the 'Get Info' window under the 'Sharing & Permissions' section, that my user account is the only account that can Read & Write files created by me.

Below is a screenshot of the default file permissions for my user account in Lion. All files that I create on my Mac have these settings.



Basically, what I would like to know is how do file permissions work. So for example if I create a TextEdit file (like in the screenshot) and my account is the only account that has permissions to Read & Write, what happens if I email the file to someone? Will they get an error message of some sort when they try to edit it?

I have some files stored on a backup HDD (with these permission settings), If I reinstalled Lion and manually moved my files back from my backup HDD would this cause issues because my original user account is not longer there? Hope that makes sense.

I am just trying to understand how the permissions work, so I hope some of you can explain.

Thanks

AJ

 

[GGJstudios]

if I create a TextEdit file (like in the screenshot) and my account is the only account that has permissions to Read & Write, what happens if I email the file to someone? Will they get an error message of some sort when they try to edit it?

No. Those permissions only relate to your Mac. They do not affect other computers.

I have some files stored on a backup HDD (with these permission settings), If I reinstalled Lion and manually moved my files back from my backup HDD would this cause issues because my original user account is not longer there? Hope that makes sense.

If you move files from a backup to your Mac, you would have the ability to change the permissions to whatever you choose.

Understanding File System Permissions | Mac OS X Support Essentials: File Systems | Peachpit
Mac OS X 10.6 Help: Setting permissions
Troubleshooting permissions issues in Mac OS X

 

[Mal]

When you email a file to someone, the permissions don't carry over with that file. Permissions are local, on your machine. If you copy over a local network to another machine, the permissions usually transfer to whatever user account you used to authenticate over the network. For the most part, you can safely assume that permissions will not affect anything you're going to do with the files.

In the case of your hypothetical scenario, you may have some trouble if you don't create a new account with the same name on the newly reinstalled system, but that can be remedied by changing the settings in the window you posted. You can also Get Info on the drive and check the box for "Ignore Ownership on this volume" to avoid any problems (although this does not work if you use the drive for Time Machine backups). Time Machine will work around these issues for files stored in it's backups.

jW

 

[.AJ]

Thanks for your speedy replies.

Thanks

AJ

 

[GGJstudios]

Thanks for your speedy replies.

I was just wanting to ensure if I have a manual backup (i.e. just copied my files from Finder) that I won't encounter any weird issues if I did a completely fresh reinstall. So from what you guys said, I wouldn't get any issues?

No, you shouldn't have any problems with that..

 

[.AJ]

Unless you plan to implement a centralized network user database so all your Macs do share the same user account database, ownership on external volumes will have to be ignored to prevent access issues. This is the default behavior on Mac OS X for all external volumes.

I found this information in the link GGJstudios posted, which clarifies my issue.

I thought I would post it up just in case anybody should have similar queries in future.

Again, thanks for your help.

AJ