CREATING File

    CREATING FILES

We can create files with generally 4 commands in centos7

1)  cat

2)  touch

3)  vi

4)  vim

1)  “cat ” command

It is used to create text file, It is also used to append (upgrade) text files. Used to view the content of the file without opening it.

cat > filename	To create file with cat
cat filename	To view the file
cat>> filename	Create and edit file

2)  “touch” command

Used to create empty file. It can create multiple empty file at the same time.

Command	Work
touch f1	To create a empty file.
touch f1 f2 f3	To create multiple empty file
touch /root/Documents/fs	To create file in particular location.
touch  /root/Desktop/file1   /root/mnt/file2	To create file in different location same time.
touch “kuldeep malviya”	To create single file with space in name.
touch .kuldeep	To create hidden file.

Creating Directory

Command = mkdir filename

1.   Used to create directory

2.   Can create multiple directory at same time

3.   Can create a tree structure of directory

Command Name	Work
mkdir filename	To create folder at current location
mkdir file1 file2 file3 file4 file5	To create multiple folder at current location
mkdir  /mnt/folder	To create folder at specified location
mkdir {1..5} filename	To create 5 folders at a time
mkdir –p A/B/C/D/E/F/G/H/I/J/K	To create tree structure (folder in folder)
du –sh	To know the size of the particular location
pwd	To know the location of particular folder
which	To know the accsess file location of the particular command
man	Help
sudo	To give the access to particular command to normal user

                           

           Copy and Move file and folders

            cp command is used to copy files and directory

·      mv command is used to move file and folder

Command	Work
cp source  destination	To copy file
cp –r source  destination	To copy folder
cp –r source/*  destination	To copy all data inside folder
cp source/name1  destination/ name2	To copy & rename
cp source/file1 destination%file2	To copy , Rename and hide file/folder
mv  source  destination	To cut (move) file /folder
mv file1  .file1	To hide existing file
mv file1   file2	To rename existing file
mv .file1  file1	To unhide file

                                                                                 

                                     Linux Directories

Directory	Use
/boot	Contain booting file.
/root	Home directory of root user.
/home	Contain the home directories of all user by default.
/etc	Contain all configuration files.
/var	Contain log messages.
/bin	Normal commands execution directory.
/sbin	Administrative commands execution directory.
/proc	Current process.
/media	External media device mount point (Graphically).
/mnt	Network or local mount point (command line ).
/opt	3rd party /software installation dir.
/usr	Entire installation and own software’s installation dir.
/lost & Found	Recovery directory (only available in the folder where any partition is mounted ).
/dev	Contains the information of all hardware components.
/tmp	Contains temporary files. Automatically delete the file which is not modified from last 10 days.
/var/tmp	Contains Temporary files. Automatically delete the file which is not modified from last 30 days.

                                   

                                       File Editor

1>  Vim

2>  Vi   

Vi and vim are the file editor which can be used to create file or edit existing files

-  There are 3 different modes in this editors 

1) Command Mode – ( By default )   

2) Insert Mode – ( Text editor ) – Press i to get in insert mode

3) Execution Mode – (Exit editing for save /unsaved exit )

Switching between vim editor’s modes

Command mode à To à Insert mode = press “i” or “a”

Insert mode à To à Command mode = press “esc”

Command mode à To à Execution mode = press “ shift + : ”

Execution mode à To à Command mode = press “esc”

Command used in execution mode

In command mode we can –

1) Copy à line , word , character

2) Cut/delete à line , word , character

3) Paste à line , word , character

4) Search à line , word , character

5) Undo / Redo

6) Replace

Commands for Line

·       To copy line = yy

·       To copy 3 line = 3yy

·       To copy n no of line = nyy

·       To paste line = p

·       To delete /cut line = dd

·       To delete n no of line = ndd

Commands for word

·       Copy word = yw

·       Copy n no. of word = nyw

·       Paste word = p

·       Delete word = dw

·       Delete n no. of word = 3dw

Commands used for character

·       Copy character = yl

·       Copy  n no. of character = 3yl

·       Paste character = p

·       Delete character = dl

·       Delete n no. of character = 3dl

Other commands

·       To set numbers in the lines = :set nu

·       To unset the line numbers = :set nonu

·       To search any word = /word name

·       To go to the end of all lines ( bottom ) = shift + G

·       To go to at the top in a slot = ctrl + u

·        

Commands used in execution mode 

·       To save file = :w

·       To quite the file ( without save ) = :q

·       To save & quite = :wq

·       To save file forcefully = :w!

·       To quite file forcefully = :q!

·       To replace any word in file = :;%s/word name