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→Default filesystem permissions: amplify role of umask wrt other chmod, setfacl, etc
m (→Default filesystem permissions: grammar) |
(→Default filesystem permissions: amplify role of umask wrt other chmod, setfacl, etc) |
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| 002 || u=rwx,g=rwx,o=rx || Files are readable and executable by everyone, but writable only by their owner and their group | | 002 || u=rwx,g=rwx,o=rx || Files are readable and executable by everyone, but writable only by their owner and their group | ||
|} | |} | ||
The umask is not the only thing that determines who can access a file. | |||
* A user trying to access a file must have execute permission on all directories in the path to the file. For example, a file might have <code>o=rx</code> permissions but an arbitrary user could not read or execute it if the parent directory does not also have <code>o=x</code> permission. | |||
* The user trying to access a file based on its group permissions must be a member of the file's group. | |||
* You can explicitly change the permissions on a file or directory after it is created, using <code>chmod</code>. | |||
* Access Control Lists (ACLs) also determine who can access a file. | |||
=== Change of the default <code>umask</code> on Cedar, Béluga and Niagara === | === Change of the default <code>umask</code> on Cedar, Béluga and Niagara === | ||
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This will mean that more restrictive permissions will be enforced on newly created files. If you need more permissive permissions for your workflow, you can change your default <code>umask</code> in your <code>.bashrc</code>. Our general advise is however to keep the default permissions. | This will mean that more restrictive permissions will be enforced on newly created files. If you need more permissive permissions for your workflow, you can change your default <code>umask</code> in your <code>.bashrc</code>. Our general advise is however to keep the default permissions. | ||
Note that | Note that this change does ''not'' mean that your files have been inappropriately exposed in the past. Restrictive access permissions have been set on your home, project, and scratch directories since the beginning. Unless the permissions were changed to give ''execute'' permission on one of these folders to others, your files still cannot be accessed by other people. | ||
=== Changing the permissions of existing files === | === Changing the permissions of existing files === | ||