Linux Module 1

What mode in VIM enables you to add text to a document?

Insert

nohup (Linux Command)

Makes process run after a user logs out

uname

Print system information. Be aware of the following uname options: -a prints all system information. -o prints the operating system. -p prints the processor's architecture type.

sort command

Puts lists in ascending or descending order according to specified keys

rmdir

Removes an empty directory

SIGHUP

Restarts a daemon

sudo command

Run command with the security privileges of the superuser (Super User DO)

bash

The Bourne again shell (Bash) is a common application to offer a shell command line; other common shell applications are the C shell, the Bourne shell, and the Kern shell.

touch command

The command used to create new files. It was originally used to update the time stamp on a file.

top command

The command used to give real-time information about the most active processes on the system; it can also be used to renice or kill processes.

locate command

The command used to locate files from a file database.

ps command

The command used to obtain information about processes currently running on the system.

userdel command

The command used to remove a user account from the system.

jobs command

The command used to see the list of background processes running in the current shell.

user-defined variables

The variables that are created by the user and are not used by the system. These variables are typically exported to subshells.

dash

Ubuntu shell

redirector >

a linux command to send the content of one file to another file

command option

a modifier

clear command

blanks the terminal screen erasing previously displayed output

What color are directories in Linux Bash?

blue

Ctrl C

cancel current command or leave Setup mode if you accidentally get into it

cd command

change directory

join command

combines the contents of each line of the source files and displays the output as a combined-single line for each line in the source files.

pr command

convert a text file into a more appropriately formatted file with the headers, pagination, and column fills. With the -d parameter, you can add double space between lines.

cp command

copy a fie

wc command

count the lines, words, and characters of a file.

rm command

deletes files

od command

displays the contents of a file in octal format (numeric base 8 format).

Split command

divide the contents of a file into multiple files. You need to specify the number of lines that you want to divide into multiple files. You also provide the name of the file as the standard output.

What files are green in Linux bash

executable

expand command

filter that converts tabs to spaces, without affection the source file

history command

history of all commands given in a program

What vi character navigation method is supported even across distributions or terminal methods?

j, k, h, l

What features are available in the vim editor that are not available in vi?

line numbers

nano

linux text editor

nl command

number the lines of a file -a number all lines in a file. -t number only the nonempty lines.

paste command

paste the output from multiple files into a vertical format.

Command Arguments

point at a specific thing

pwd

print working directory

man command

read the online manual page for a command

ls -l -a (ls -la)

shows all files in long list including hidden files

~ in Linux command Line

shows you are in root directory

su command

substitue user.

vi command

text editor

unset command

unsets a variable

mv command

used to both move a file to a new directory, and to rename a file.

fmt command

used to define uniform spacing between words and sentences. When used with the -u parameter, it formats the text with one space between words and two spaces between sentences.

cut command

used to print the selected output of a file onto screen. However, the source file remains as is and no modifications are made to it.

What color are text files in Linux bash?

white

What vi command would copy the current line into the buffer?

yy

What vi command exits a document without saving?

:q!

dd command

A Linux command that can be used to write image files to a device such as a USB flash memory drive or hard disk.

head command

A Linux command that displays the first set of lines of a text file; by default, the head command displays the first 10 lines.

grep command

A Linux command that searches files for patterns of characters using regular expression metacharacters. The command name is short for "global regular expression print."

cat command

A Linux command used to display (or concatenate) the entire contents of a text file to the screen.

more command

A Linux command used to display a text file page-by-page and line-by-line on the terminal screen. less command scrolls only down, whereas more enables you to scroll down and up.

tail command

A Linux command used to display lines of text at the end of a file; by default, the tail command displays the last 10 lines of the file.

ls command

A Linux command used to list the files in a given directory.

uptime command

A command that displays the amount or percentage of time a computer system or associated hardware is functioning and available for use.

Find command

A command to help you search for certain content.

alias command

A command used to create special variables that are shortcuts to longer command strings.

env command

A command used to display a list of exported variables present in the current shell, except special variables.

free command

A command used to display memory and swap statistics.

The echo command:

A command used to display or echo output to the terminal screen. It might utilize escape sequences.

kill command

A command used to stop or abort a process in a program or operating system.

set command

A command used to view all variables in the shell, except special variables.

sed command

A filter command used to search for and manipulate text.

fgrep command

A variant of the grep command that does not allow the use of regular expressions.

egrep command

A variant of the grep command, used to search files for patterns using extended regular expressions.

What commands require super user privileges?

Commands that affect the whole system commands that affect a user other than your own

/usr/bin

Contains the executable programs installed by your Linux distribution

mkdir

Creates a directory

ls -l

Display results in long format

whoami

Display the current username

environment variables

Environment variables are like variables in programming languages—they hold data to be referred to by the variable name. Environment variables differ from programs' internal variables in that they're part of the environment of a program, and other programs, such as the shell, can modify this environment.