From the course: Linux: Files and Permissions

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Initial permissions using umask

Initial permissions using umask - Linux Tutorial

From the course: Linux: Files and Permissions

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Initial permissions using umask

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- [Instructor] When files are created, initial permissions are applied automatically. These permissions are calculated based on a bit mask called umask. To see your umask, type into a terminal, umask, and hit enter. We can also view the umask in symbolic notation by using the -S option. Type in umask -S and hit enter. The umask can have either three characters or four. Feel free to add the leading zero or leave it off for standard permissions. Notice that the umask isn't the same format as numeric permission, such as 754 is actually upside down, since it's a mask. To calculate initial permissions we'll have to subtract the umask from maximum allowed initial permissions, based on whether the item is a file or a directory. For directories our maximum initial permission are 777, since having execute on a directory does not create a security risk. Let's use a umask of 022. Now let's subtract the umask from the…

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