Linux+ Chapter 3
tac command
A Linux command that displays a file on the screen, beginning with the last line of the file and ending with the first line of the file.
file command
A Linux command that displays the file type of a specified filename.
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."
cd (change directory) command
A Linux command used to change the current directory in the directory tree.
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
A Linux command used to display a text file page-by-page on the terminal screen; users can then use the cursor keys to navigate the file.
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.
od command
A Linux command used to display the contents of a file in octal format.
pwd (print working directory) command
A Linux command used to display the current directory in the directory tree.
ls command
A Linux command used to list the files in a given directory.
strings command
A Linux command used to search for and display text characters in a binary file.
gedit editor
A common text editor used within GUI environments.
home directory
A directory on the filesystem set aside for users to store personal files and information.
subdirectory
A directory that resides within another directory in the directory tree.
Tab-completion feature
A feature of the BASH shell that fills in the remaining characters of a unique filename or directory name when the user presses the Tab key.
executable program
A file that can be executed by the Linux operating system to run in memory as a process and perform a useful function.
binary data file
A file that contains machine language (binary 1s and 0s) and stores information (such as common functions and graphics) used by binary compiled programs.
log file
A file that contains past system events.
text file
A file that stores information in a readable text format.
special device file
A file used to identify hardware devices such as hard disks and serial ports.
~ metacharacter
A metacharacter used to represent a user's home directory.
socket file
A named pipe connecting processes on two different computers; it can also be represented by a file on the filesystem.
Emacs (Editor MACroS) editor
A popular and widespread text editor more conducive to word processing than vi. It was originally developed by Richard Stallman.
vi editor
A powerful command-line text editor available on most UNIX and Linux systems.
filename extension
A series of identifiers following a dot ( . ) at the end of a filename, used to denote the type of the file; the filename extention .txt denotes a text file.
directory
A special file on the filesystem used to organize other files into a logical tree structure.
named pipe file
A temporary connection that sends information from one command or process in memory to another; it can also be represented by a file on the filesystem.
nano editor
A user-friendly terminal text editor that uses Ctrl key combinations to perform basic functions.
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.
ll command
An alias for the ls -l command; it gives a long file listing.
command mode
One of the two modes in vi; it allows a user to perform any available text-editing task that is not related to inserting text into the document.
insert mode
One of the two modes in vi; it allows the user to insert text into the document but does not allow any other functionality.
parent directory
The directory that is one level closer to the root directory in the directory tree relative to your current directory.
linked file
The files that represent the same data as other files.
absolute pathname
The full pathname to a certain file or directory starting from the root directory.
concatenation
The joining of text together to make one larger whole. In Linux, words and strings of text are joined together to form a displayed file.
wildcard metacharacters
The metacharacters used to match certain characters in a file or directory name; they are often used to specify multiple files.
relative pathname
The pathname of a target directory relative to your current directory in the tree.
text tools
The programs that allow for the creation, modification, and searching of text files.
regexp
The special metacharacters used to match patterns of text within text files; they are commonly used by text tool commands, including grep.
regular expressions
The special metacharacters used to match patterns of text within text files; they are commonly used by text tool commands, including grep.
filename
The user-friendly identifier given to a file.
