| | 1 | = How do I know if a file is world readable? How can I change that? = |
| | 2 | |
| | 3 | On a typicaly linux system, there are three sets of permissions: |
| | 4 | |
| | 5 | * user: the permissions for the person who owns the file |
| | 6 | * group: the permissions for users who are in the group assigned to the file |
| | 7 | * other: the permissions for everyone else who has an account on the server |
| | 8 | |
| | 9 | Each set of permission can have three values: |
| | 10 | |
| | 11 | * write access |
| | 12 | * read access |
| | 13 | * execute access |
| | 14 | |
| | 15 | The first two are self-explanatory. The third (execute access) has two different meanings: |
| | 16 | |
| | 17 | * For a directory, it means that you can enter the directory and get details of the files in the directory |
| | 18 | * For a file, it means you can execute the file (required if the file is a program) |
| | 19 | |
| | 20 | If you are using [wiki:sftp an SFTP program] to access your directories, the method for will vary depending on the program you are using. If you are using WinSCP, simply right click on the file or folder and click properties. You will see the current permissions and be given an opportunity to change them. |
| | 21 | |
| | 22 | If you are using [wiki:secure_shell secure shell] you can change the mode of a file or directory with the `chmod` command. For example: |
| | 23 | |
| | 24 | {{{ |
| | 25 | # remove read access from others |
| | 26 | chmod o-r foo.txt |
| | 27 | |
| | 28 | # remove read access from the group |
| | 29 | chmod g-r foo.txt |
| | 30 | |
| | 31 | # remove read and execute from all users execpt the owner |
| | 32 | chmod o-rx foo.txt |
| | 33 | chmod g-rx foo.txt |
| | 34 | |
| | 35 | # Add read and execute access for everyone |
| | 36 | chmod o+rx foo.txt |
| | 37 | }}} |
