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List of results

Memory + (Memory is the fundamental element in conventional contemporary computers, (apparently) containing all the code and data of executing programs. Its management as a resource is a fundamental task.)
Metadata + (Metadata provides information about the ‘main’ data.)
Using Peripherals + (Methods by which the software can communicate with the I/O devices.)
Mutual exclusion + (Mutual exclusion means “one at a time”. In this case it is largely about only allowing one of many possible threads to change some structure or I/O device.)
Pointers + (Not restricted to OS code, pointers are used in all computer programming. They are used extensively in (and around) an OS and a thorough understanding is important.)
System Calls + (OS provided calls that provide privileged, protected services using trusted code. Used to provide access to I/O devices, system variables etc.)
Virtual Machines + (One 'box' can apparently be several independent computers.)
Virtual Networks + (One wire can support several independent connections.)
Monitoring page behaviour + (Optimisations can require the collection of information about behaviour. This looks at some approaches to finding the information using limited hardware support.)
PATH + (Ordered lists of places to look for something.)
Pipes + (Pipes are a convenient means of allowing processes to communicate. One process sends output into a pipe and another can read it from the other end when it wants to.)
Processes + (Processes are running programs. Many computers run - or appear to run - many processes simultaneously.)
File Locking + (Protecting files from confusion.)
Real Time + (Real time systems are those where a late answer is always a wrong answer. It is a requirement in, for example, control systems such as autonomous vehicles.)
Page Eviction + (Schemes for deciding/predicting which parts of memory are not really wanted too much, and won't be in the (near) future).)
Concepts + (Some 'highlight' principles which are widely applicable to operating systems and a range of other computing applications.)
Shell Scripting + (Some examples of jobs which can be done easily with simple ‘command line’ scripts.)
Bibliography + (Some further reading in a more "conventional" form.)
Interprocess Communication + (Some high-level notes on how two or more independent processes may communicate.)
Pointer Exercise + (Some practice (for beginners in C) in how to get at memory 'directly'.)
Software Exceptions + (Some processors will trap to the O.S. when the processor encounters an execution anomaly - e.g. division by zero.)
Errors + (Some run time errors are unavoidable. They should still be considered and handled in a defined way.)
Operation Ordering + (Sometimes the order in which operations are performed is vitally important - especially in a multi-threaded environment.)
Atomicity + (Sometimes two (or more) operations need to be performed 'simultaneously'. Since software cannot do this there need to be mechanisms to ensure no outside operations interfere.)
Process Priority + (Sometimes, some processes may be more important or urgent than others. Priority schemes can provide a greater share of resources (particularly processor time) for selected tasks. This can be particularly important in real-time systems.)

Introduction to Operating Systems + (Start here! This links to the major, top-level concepts.)

Acknowledgements + (Thanks to contributors to this site.)
Application Binary Interface (ABI) + (The Application Binary Interface specifies the way software elements communicate within a program.)
Synchronisation + (The act of collecting together disparate threads so all are at definitive points in their execution.)
Process States + (The basic data behind scheduling processes.)
Kernel + (The central, essential part of an operating system. Approaches vary.)
Context + (The context is the state of a running process.)
Paging + (The mechanism by which memory mapping is usually managed.)
Process Scheduling + (The process of sharing the processor (or other) time amongst competing needs.)
Scheduler + (The schedule is the routine or algorithm which decides what to do next.)
Virtual Memory + (The separation of the user's view of memory and the physical reality on any given machine. Usually involves translating addresses and may employ paging from backing store.)
File Attributes + (The sort of metadata which accompanies every file.)
File Descriptor + (The system used to maintain an open file.)
Memory Segmentation + (The way memory is organised into logically consistent areas.)
Filing System Implementation + (There are many ways of constructing a file system, even if different mechanisms look the same to a user. Here are some examples.)
Peripheral devices + (These are the hardware interfaces which provide the physical I/O for the computer. There may be a large variety in any given system.)
Structures + (This article covers software collections of associated variables (usually with mixed types) as in a C ‘struct’ or the data in a Java object.)
About this resource + (This describes the major features of this site.)
Threads + (Threads are separate code sequences which can be executed in parallel. In general, one process can have several threads with the same memory context.)
Man(ual pages in Unix) + (Unix on-line manual.)
Streams + (Unstructured, serial data communications channels.)
Monitoring + (Watching what is going on.)
File Types + (What sort of thing is in this file?)
Idle + (What a processor does when there's nothing better to do.)
Boot + (What processes might run as a computer starts up?)
File Permissions + (Who is allowed to do what to a file.)