Thursday, July 24, 2014

Customizing the UNIX User Environment - Part 4 - UNIX documentation - Part 1

Customizing the UNIX User Environment


UNIX documentation


UNIX system documentation refers to reference material, which is in the form of both online and hard copy tutorial documents and manuals. The system documentation enables a user to access help information on how to install UNIX and use UNIX commands and utilities.

The system documentation may include the online manual, commonly referred to as "the man pages," info pages, and instructions in "readme" files, which are sometimes provided with applications. Although documentation is usually available in an electronic format, hardcopy documentation is sometimes provided with a system.


Overview of the online manual


The UNIX online manual - known as the man pages - contains explanations of all the UNIX commands.

You can use these explanations as a handy reference to find out what a particular command does

You can also use it to search for a task you want to perform


The online manual includes the following sections

commands - The user commands section contains help information on UNIX commands that ordinary users can access

systemcalls - contains help info on functions that only the kernel provides

subroutines - contains help information on library functions

special files - contains help info on devices listed in the dev directory

file formats - contains help info on file format descriptions for example /etc/passwd

macro packages and conventions - contains info on miscellaneous apps

games - contains info on games installed on a computer system

system maintenance - contains help info about system administration tools executable by the root


Subroutines (add info) - Third party library APIs are supplied to perform tasks which are not included in the default installations. You can program against these libraries using an appropriate language, such as C++. The suppliers of the livraries include their own man pages that descrine each function and how to use it.


System Calls (add info) - By virtue of the kernel UNIX allows many programs to run simultaneously by giving each one the illusion that it exists on its own private virtual-machine. Calls from your applications to the kernel are known as system calls. You can use the trace command to see the system calls that a particular application generates.


System Maintenance (add info) - Administration function allows you to maintain a UNIX system. For example, they allow you to gather details on a specific user(finger), determine who is currently logged on (who is), and remove a specific process(kill).









No comments:

Post a Comment