Mastering the command line - a new reference book
I hope this is acceptable to the community as I am trying to make a contribution to the open source community by sharing a book that I just wrote. The 340 page book can be downloaded as a PDF. However, you can also clone my project as the book is a compiled LaTex document (and thus learn something about writing a book using the LaTex typesetting system). The book covers these topics: command line/scripting, creating bash profiles, mastering the manpage, the vi text editor, using the find command, setuid/setguid/sticky-bit, ACLs, simple file tricks, managing users/groups, managing processes, dnf, compression/archiving, network processes, and SELinux. The book is based on the Fedora operating system, but most commands should work on other flavours of Linux. You can get the book at either my github project page: https://github.com/murraydavis/Linux-System-Administration or via its clone at Sourceforge: https://sourceforge.net/projects/linux-system-administration/.