The IP protocol is a transport layer that is used by other protocols to carry their data. As the cliche goes, "If we both have an apple, and we exchange apples, we each still have one apple. It provides the interfaces documented in SUSv4 and POSIX 2008, including real-time (POSIX …

For kernel code, once it is complete the developer may ask Linus to include it in the standard kernel, or as an optional add-on feature to the kernel. An inode stores metadata associated with a file, such as its modification timestamp, owner, type, length, and the location of the file's …

Linux is open-source. With all the activity around Unix at Berkeley, a new delivery of Unix software was born: the Berkeley Software Distribution, or BSD. Furthermore, the developer writing Python or Ruby or Scala can still benefit from knowledge of system programming, as an understanding of the soul of the …

Public domain refers to the total absence of copyright protection. Normally, Linux would suspend the requestor, putting the process onto a wait queue until there is enough physical memory. It sounds counterintuitive and/or just plain stupid on paper, but is generally seen as the traditional and conservative way to …

Linux (as well as many other areas of information technology) is particularly well suited for studying at home because (1) no equipment is needed other than an ordinary personal computer and (2) there is a large amount of free or modestly priced study material that is available from bookstores, in …

In addition to the real uid, each process also has an effective uid, a saved uid, and a filesystem uid. The terminal in Linux is a wild card. Whereas sockets communicating over the Internet might use a hostname and port pair for identifying the target of communication, Unix domain sockets …