Commands Flashcards
(54 cards)
cd
The “Change Directory” command enables you to navigate to another directory. As the command suggests, it enables the user to change / jump to a directory.
Example: cd Downloads
Example: cd /etc/
Example: cd .. (Directory up!)
man
The man command shows the users the “manual” of the command. In some situation you might need to get more information about the command you are using. The man command shows you this information about the command. Example: man cp
This will open up the “cp” manual document for us in the shell. The manual shows us the parameters available for the commands.
note: To close the manual simply press “Q”.
ls
The ls command is used to list the files/directories within a directory.
Example: ls
It shows us the directories available.
cp
The cp command is available for us to “Copy” things. This might be usefull for duplicating files f.e.
Example: cp file file2
note: file is on this case the file the user wants to be copied… file2 is the name of the copied file.
mv
The mv command is used for “Move” operations. The mv commands enables the users to move a file/directory to a specified location.
Example: mv /home/bas/Desktop/bla /home/bas/Desktop/fiets
note: the first part of the command is the file that has to be moved. The second part (after the whitespace) is the target directory. Make sure you type in the full path using this command!
mkdir
This command is used to “make” directories, NOT Files.. (thit is possible with another command which i will bring up later in this tutorial)
Example: mkdir testdirectory
note: The name of the directory is case sensitive which means that Testdirectory is a complete different directory as testdirectory.
rmdir
When you are able to make directories, you also want to know how to remove them. Removing directories is done by the rmdir command and belongs to the absolute basic commands in shell bashing.
Example: rmdir fiets
note: When the directory is not empty the command will prompt an error message:
rmdir: failed to remove `fiets’: Directory not empty
So make sure it’s completely empty before removing it.
touch
Now we know how to make directories and deleting them, i now want to use the touch command. The touch command is used to make files.
Example: touch vogel
This will create the file vogel for us in the directory.
rm
The rm command stand for remove. The rm command is used in order the delete files instead of directories.
Example: rm vogel
note: To remove files you must have the right permission bits set on the specific file.
tar
Sometimes you have to archive files. Archiving files is a way to pack a set of files to one single file. The operation is done by the tar command.
Example: tar -cvf test.tar test (Creating a tar file from directory or file test)
Example: tar -xvf test.tar myexctractfolder (Extracts the particular tar file in the current working directory)
In the example i used parameters. These parameters are telling the tar command how to behave and how to execute. After the parameters i entered the name of the file which is test.tar. The second part is the source directory/file of the tar file. In this situation a directory called test.
pwd
Sometimes you really wonder where you are in the system. PWD is the solution for that problem.
PWD stands for Path Working Directory.
ifconfig
ifconfig is a command showing you information about the ethernet adapters on your system. It contains very usefull information like gateway, ip, and packet statistics. For the average user this command is rarely used, but i think it’s worth knowing it.
Example: ifconfig
note: To gain information about the wireless adapters on your system type iwconfig.
locate
Locate is an extremely fast seaching command. It shows the directories or files each on a new line.
Example: locate syslog
Example: locate syslog | more (Piping structure used to invert the data from locate to the more command)
note: Some keywords returns enormous ammounts of hits. Use MORE to (see example) clear things up a bit.
chmod
To change permissions
cat [filename]
Display file’s contents to the standard output device
usually your monitor
chown (options) filename
Change who owns a file
clear
Clear a command line screen/window for a fresh start
date
display or set the system date and time
df (options)
display used and available disk space
du (options)
show how much space each file takes up
file (options) filename
determine what type of data is within a file
find {paththname} {expression}
search for files matching a provided pattern
find files using filename (case in-sensitive find):
# find -iname “MyCProgram.c”
find all empty file in home directory
# find ~ -empty
grep [options] pattern [filesname]
search files or output for a particular pattern
kill [options] pid
stop a process. If the process refuses to stop, use kill -0 pid
