Go to TogaWare.com Home Page. GNU/Linux Desktop Survival Guide
by Graham Williams
Duck Duck Go

File and Directory Protections

The setgid bit on a directory (in the group-execute portion represented as an s or S) forces all files to be created in the directory with the group of the parent directory rather then the user's primary group. This is the BSD file creation semantics rather than SYSV.

By default Debian uses a umask of 755. It is a long and well known Linux tradition to create home directories world readable as it encourages a sharing environment. Users can always change the permissions on their home directory or any subdirectory they want to keep private.

To change this default behaviour edit /etc/adduser.conf to change the DIR_MODE option.


Support further development by purchasing the PDF version of the book.
Other online resources include the Data Science Desktop Survival Guide.
Books available on Amazon include Data Mining with Rattle and Essentials of Data Science.
Popular open source software includes rattle and wajig.
Hosted by Togaware, a pioneer of free and open source software since 1984.
Copyright © 1995-2020 Togaware Pty Ltd. . Creative Commons ShareAlike V4.