Chapter 3 (Using the Shell) Flashcards
(36 cards)
A — is like a program or a macro
Script
A — is essentially a list of commands stored in a text file.
Script
The default shell for all Linux systems is —
Bash
Changing to a new default shell is very easy using the — command.
usermod
The – — records each command that you enter at the shell prompt.
Command History
The — command displays the entire history list, which normally includes at least — commands
History, 1000
A exclamation point is sometimes called a – in unix and Linux
bang
The — script contains configuration information that applies to every user on the system.
/etc/profile
Each users home directory can contain another start-up script called—
.profile
The — script is executed each time the user starts a bash shell.
.bashrc
(Bash Scripts)
— is executed each time a bash shell is started.
.bash_default
.bash_login
(Bash Scripts)
— is executed each time a user closes a bash shell
.bash_logout
A — is a string of characters that is substituted for another string of characters at the shell prompt.
Alias
The — command lets you define how the shell will substitute one string of text for another string of text that you enter at a shell prompt.
Alias
(Alias example)
alias muont=mount
The — command writes text to the screen.
Echo
As used in a Linux shell, is a name that can have a value assigned to it.
Shell variable
(Note)
Variables are typically created using all uppercase letters, though they don’t have to be. `
|
You can use the — command to start a program with an environment variable setting that is not part of your current environment.
env
An — — is a variable that has typically been defined (assigned a value) as part of the process of initializing either the operating system or the particular shell in which a user is working.
Environment Variable
The — command displays a list of all environment variables defined in your current environment.
set
Example $ set
Channels of communication in Linux can be redirected, however, using — operators
Redirection
When a program expects input such as a line of text, it reads that information from the standard — – – channel.
Standard Input channel (abbreviated STDIN)
When a program generates output, it normally sends it to the — — —
Standard output channel (abbreviated STDOUT)