Tag: command

Show Disk Usage – du

du shows the ‘disk usage’ – the space taken up by the files and folders in the current directory. du…

free Command

free gives the Memory info (in kilobytes). free #Output total used free shared buffers cached Mem: 2075000 667508 1407492 0…

last Command

The last command shows a history of logins… last

Double Space a File using Sed

Add a \n after every line in a file using the sed command… sed G

Finger Command

System info about a user. Try: finger root. An admin needs it all the time finger user_name #finger root Login:…

cmp Command – Compare Files

The command cmp is similar to diff: # cmp file1 file2 file1 file2 differ: byte 10, line 1

Find Current IP Address

Find the IP address of all the active interfaces. ifconfig | egrep -o ‘^[a-z0-9]{1,12}|inet addr:[0-9.]+’

Basic Diff

If you use the diff command, you will be able to see the difference between the files as shown below:…

whereis command

Find where the command executable is located… whereis perl

Using M4 Command

This command takes an input file and substitutes strings inside it with the parameters passed, similar to substituting for variables….