0 Linux Basic Commands

Here is a list of basic Linux commands Very usefull i suppose.

For changing directory / to /etc
[root@pc1 /]# cd /etc 

 
One step back /etc to /
[root@pc1 etc]# cd .. 
 

Go to previous working directory
[root@pc1 /]# cd - 
 

Go to current login user home directory
[root@pc1 etc]# cd ~ 
 

Show the contents of /etc in single color
[root@pc1 ~]# dir /etc 
 

Show the contents of /etc in different colors with nature of contents
[root@pc1 ~]# Ls /etc 
 

create a folder on root partition
[root@pc1 ~]# mkdir /disk 
 

Create a folder in /disk
[root@pc1 ~]# mkdir /disk/dir 
 

Create multiple folder in multiple directories with single command
[root@pc1 ~]# mkdir /etc/dir1 /var/dir2 /usr/dir3 
 

Create multiple folder in same directory
[root@pc1 ~]# mkdir dir1 dir2 dir3 
 

Copy a file in directory
[root@pc1 disk]# cp file dir 
 

Copy a file from /disk/file and paste it in /disk/dir/
[root@pc1 disk]# cp /disk/file /disk/dir 
 

Copy a directory with –r option
[root@pc1 disk]# cp -r dir dir2 
 

Copy a file from /disk/file and paste it in /etc with myfile name
[root@pc1 disk]# cp /disk/file /etc/myfile 
 

Remove a file
[root@pc1 disk]# rm file 
 

Remove a file with forcefully option
[root@pc1 disk]# rm –f file 
 

Remove a directory with out –r option and you face will an error
[root@pc1 disk]# rm dir 
 

Remove a directory with –r option
[root@pc1 disk]# rm -r /disk 
 

Remove a directory with forcefully option
[root@pc1 disk]# rm -rf dir 
 

Move /etc/dir1 to /disk/ with different name
[root@pc1 disk]# mv /etc/dir1 /disk/mydir 
 

Rename the folder name mydir to dir
[root@pc1 disk]# mv /disk/mydir /disk/dir 
 

Rename the file name with myfile
[root@pc1 disk]# mv file myfile 
 

Read a file page by page with less command
[root@pc1 disk]# less /etc/grub.conf 
 

Read a file page by page with more command
[root@pc1 disk]# more /etc/qrub.conf 
 

Read first ten lines of grub.conf
[root@pc1 disk]# head /etc/grub.conf 
 

Read last ten lings of grub.conf
[root@pc1 disk]# tail /etc/grub.conf 
 

Read first 12 lines with –n option
[root@pc1 disk]# head -n 12 /etc/grub.conf 
 

Read last 11 lines with –n option
[root@pc1 disk]# tail -n 11 /etc/grub.conf 
 

Copy the contents of /etc/grub.conf in /disk/file
[root@pc1 disk]# cat /etc/grub.conf > /disk/file 
 

Append the contents /etc/mtab in /etc/file
[root@pc1 disk]# cat /etc/mtab >> /disk/file 
 

Merging tow commands with pipe sign output of the first command is input of second command
[root@pc1 disk]# cat /etc/squid/squid.conf I more 
 

Count the total lines of squid.conf
[root@pc1 disk]# cat /etc/squid/squid.conf I wc -L 
 

Show only spool words in squid.conf
[root@pc1 disk]# cat /etc/squid/squid.conf I grep spool 
 

Flush the contents of file
[root@pc1 disk]# cat /dev/null > /var/log/messages