Tips for New Linux Users - 1

[The-REV]

This installation guide assumes that the user has at least a basic understanding of Linux techniques and terminology. In this section we provide tips that the new user may find helpful. While the these tips are meant to clarify and assist users in installing and configuring the NVIDIA Linux Driver, it is by no means a tutorial on the use or administration of the Linux operating system. Unlike many desktop operating systems, it is relatively easy to cause irreparable damage to your Linux system. If you are unfamiliar with the use of Linux, we strongly recommend that you seek a tutorial through your distributor before proceeding.

The command prompt

While newer releases of Linux bring new desktop interfaces to the user, much of the work in Linux takes place at the command prompt. If you are familiar with the Windows operating system, the Linux command prompt is ****ogous to the Windows[1] command prompt, although the syntax and use varies somewhat. All of the commands in this section are performed at the command prompt. Some systems are configured to boot into console mode, in which case the user is presented with a prompt at login. Other systems are configured to start the X window system, in which case the user must open a terminal or console window in order to get a command prompt. This can usually be done by searching the desktop menus for a terminal or console program. While it is customizable, the basic prompt usually consists of a short string of information, one of the characters #, $, or %, and a cursor (possibly flashing) that indicates where the user's input will be displayed.
Navigating the directory structure

Linux has a hierarchical directory structure. From anywhere in the directory structure, the ls command will list the contents of that directory. The file command will print the type of files in a directory. For example,
% file filename

will print the type of the file filename. Changing directories is done with the cd command.
% cd dirname

will change the current directory to dirname. From anywhere in the directory structure, the command pwd will print the name of the current directory. There are two special directories, . and .., which refer to the current directory and the next directory up the hierarchy, respectively. For any commands that require a file name or directory name as an argument, you may specify the absolute or the relative paths to those elements. An absolute path begins with the "/" character, referring to the top or root of the directory structure. A relative path begins with a directory in the current working directory. The relative path may begin with . or ... Elements of a path are separated with the "/" character. As an example, if the current directory is /home/jesse and the user wants to change to the /usr/local directory, he can use either of the following commands to do so:
% cd /usr/local

or
% cd ../../usr/local

File permissions and ownership

All files and directories have permissions and ownership associated with them. This is useful for preventing non-administrative users from accidentally (or maliciously) corrupting the system. The permissions and ownership for a file or directory can be determined by passing the -l option to the ls command. For example:
% ls -l
drwxr-xr-x 2 jesse users 4096 Feb 8 09:32 bin
drwxrwxrwx 10 jesse users 4096 Feb 10 12:04 pub
-rw-r--r-- 1 jesse users 45 Feb 4 03:55 testfile
-rwx------ 1 jesse users 93 Feb 5 06:20 myprogram
-rw-rw-rw- 1 jesse users 112 Feb 5 06:20 README
%

The first character column in the first output field states the file type, where 'd' is a directory and '-' is a regular file. The next nine columns specify the permissions (see below) of the element. The second field indicates the number of files associated with the element, the third field indicates the owner, the fourth field indicates the group that the file is associated with, the fifth field indicates the size of the element in bytes, the sixth, seventh and eighth fields indicate the time at which the file was last modified and the ninth field is the name of the element.

As stated, the last nine columns in the first field indicate the permissions of the element. These columns are grouped into threes, the first grouping indicating the permissions for the owner of the element (jesse in this case), the second grouping indicating the permissions for the group associated with the element, and the third grouping indicating the permissions associated with the rest of the world. The r, w, and x indicate read, write and execute permissions, respectively, for each of these associations. For example, user jesse has read and write permissions for testfile, users in the group users have read permission only, and the rest of the world also has read permissions only. However, for the file myprogram, user jesse has read, write and execute permissions (suggesting that myprogram is a program that can be executed), while the group users and the rest of the world have no permissions (suggesting that the owner doesn't want anyone else to run his program). The permissions, ownership and group associated with an element can be changed with the commands chmod, chown and chgrp, respectively. If a user with the appropriate permissions wanted to change the user/group ownership of README from jesse/users to joe/admin, he would do the following:
# chown joe README
# chgrp admin README

The syntax for chmod is slightly more complicated and has several variations. The most concise way of setting the permissions for a single element uses a triplet of numbers, one for each of user, group and world. The value for each number in the triplet corresponds to a combination of read, write and execute permissions. Execute only is represented as 1, write only is represented as 2, and read only is represented as 4. Combinations of these permissions are represented as sums of the individual permissions. Read and execute is represented as 5, where as read, write and execute is represented as 7. No permissions is represented as 0. Thus, to give the owner read, write and execute permissions, the group read and execute permissions and the world no permissions, a user would do as follows:
% chmod 750 myprogram