Books / Linux Notes for Professionals / Chapter 2
File Management Commands in Linux
Linux uses some conventions for present and parent directories. This can be a little confusing for beginners.
Linux uses some conventions for present and parent directories. This can be a little confusing for beginners. Whenever you are in a terminal in Linux, you will be in what is called the current working directory. Often your command prompt will display either the full working directory, or just the last part of that directory. Your prompt could look like one of the following:
user@host ~/somedir $
user@host somedir $
user@host /home/user/somedir $
which says that your current working directory is /home/user/somedir
.
In Linux .
. represents the parent directory and .
represents the current directory.
Therefore, if the current directory is /home/user/somedir
, then cd ../somedir
will not change the working directory.
The table below lists some of the most used file management commands.
Directory Manipulation Commands in Linux
pwd
Get the full path of the current working directory.cd -
Navigate to the last directory you were working in.cd ~
or justcd
Navigate to the current user’s home directory.cd ..
Go to the parent directory of current directory (mind the space betweencd
and..
)
Listing Files Inside a Directory
ls -l
List the files and directories in the current directory in long (table) format (It is recommended to use-l
withls
for better readability).ls -ld dir-name
List information about the directorydir-name
instead of its contents.ls -a
List all the files including the hidden ones (File names starting with a.
are hidden files in Linux).ls -F
Appends a symbol at the end of a file name to indicate its type (*
means executable,/
means directory,@
means symbolic link,=
means socket,|
means named pipe,>
means door).ls -lt
List the files sorted by last modified time with most recently modified files showing at the top (remember-l
option provides the long format which has better readability).ls -lh
List the file sizes in human readable format.ls -lR
Shows all subdirectories recursively.tree
Will generate a tree representation of the file system starting from the current directory.
File or Directory - Create, Copy and Remove Commands in Linux
cp -p source destination
Will copy the file fromsource
todestination
directory.-p
stands for preservation. It preserves the original attributes of file while copying like file owner, timestamp, group, permissions etc.cp -R source_dir destination_dir
Will copy source directory to specified destination recursively.mv file1 file2
In Linux there is no rename command as such. Hencemv
moves/renames thefile1
tofile2
.rm -i filename
Asks you before every file removal for confirmation. IF YOU ARE A NEW USER TO LINUX COMMAND LINE, YOU SHOULD ALWAYS USE rm -i. You can specify multiple files.rm -R dir-name
Will remove the directorydir-name
recursively.rm -rf dir-name
Will remove the directory dir recursively, ignoring non-existent files and will never prompt for anything. BE CAREFUL USING THIS COMMAND! You can specify multiple directories.rmdir dir-name
Will remove the directorydir-name
, if it’s empty. This command can only remove empty directories.mkdir dir-name
Create a directorydir-name
.mkdir -p dir-name/dir-name
Create a directory hierarchy. Create parent directories as needed, if they don’t exist. You can specify multiple directories.touch filename
Create a file filename, if it doesn’t exist, otherwise change the timestamp of the file to current time.
File or Directory - Permissions and Groups Commands
chmod < specification > filename
Change the file permissions. Specifications =u
user,g
group,o
other,+
add permission,-
remove,r
read,w
write,x
execute.chmod -R < specification > dir-name
Change the permissions of a directory recursively. To change the permission of a directory and everything within that directory, use this command.chmod go=+r myfile
Add read permission for the owner and the group.chmod a +rwx myfile
Allow all users to read, write or executemyfile
.chmod go -r myfile
Remove read permission from the group and others.chown owner1 filename
Change ownership of a file to userowner1
.chgrp grp_owner filename
Change primary group ownership of filefilename
to groupgrp_owner
.chgrp -R grp_owner dir-name
Change the primary group ownership of directorydir-name
to groupgrp_owner
recursively. Use this command to change group ownership of a directory and everything within that directory.