Here’s how to fix write permissions for DaVinci Resolve.
To fix this, just open a terminal and run:
chmod -R 766 /your/problem/drive/or/directory
What’s Going On?
On linux, security is brilliantly built in. By default, files and folders that you create have a set level of permissions (defined by the umask command). Typically, the default is the user (you) have permission to read and write files that you own, as well as search directories you own. All others have read-only access to your files and directories.
Knowing this, other applications (aka Resolve) do not have permission by default to write to hard drives, folders, or files that you (the user) own. So how do we change this?
chmod
To change permissions of a single file or a whole directory, use the chmod command. chmod gives you the ability to change permissions using short, 3-digit number formats. These are known as octal numbers.
| Octal Number | Permissions | File Listing |
| 7 | read, write, and execute | rwx |
| 6 | read and write | rw- |
| 5 | read and execute | r-x |
| 4 | read only | r– |
| 3 | write and execute | -wx |
| 2 | write only | -w- |
| 1 | execute only | –x |
| 0 | none | — |
So in the chmod command, you use the above table to define permissions for the file user/owner, members of the file group, and other people, in that order. The -R flag used in the code above, simply makes the command recursive, applying to every single file and folder inside the directory you apply the command to.
Examples
Readable by owner only: chmod 400 examplefile.txt
Allow the owner and group to read, write, and execute, and anyone else to read and write: chmod 776 examplefile.txt
Also, there’s an awesome tool for those of you, like me, who can’t keep all those chmod codes straight!
After this post made it to Twitter, @rohit_bmd made a great point- check Davinci Resolve > Preferences and under the Media Storage tab, you’ll see a list of drives on your system. Make sure you have read/write privileges on the drive at the very top of that list, because that’s where Resolve will be storing all your cache files. Here’s the the tab:
If you’re new to Resolve on Linux, feel free to check out my other posts.