UNIX environment check

1. How to check the shell you are running?

ps utility can show the current shell you are working with.

>ps

PID TTY          TIME CMD
2549 pts/0    00:00:00 bash
2598 pts/0    00:00:00 ps

2. How to change to superuser / root privilege in unix?

>sudo su -

This command will ask for passoword and once it is give the prompt will also chnage to "#" . Be careful the with root privilege you can modify systems files.

3. How to change password in unix?

Give the command passwd .It will ask for the current password and the new password.

>passwd
Changing password for user.
(current) UNIX password:
Enter new UNIX password:

4. How the check the environment you are working on ?

>hostname

This will display the environment on shell.

5. To display which all users have logged in .

>who
user :0           2015-04-25 16:35 (:0)user pts/0        2015-04-25 16:40 (:0)user pts/16       2015-04-25 17:20 (:0)

The first cloumn is showing the name of user. The second column is showing the device to wich each user's terminal emulator is connected to. The third column is the date and time each user has logged in.

6. To display which terminal I am using and login time.

>who am i
user pts/16       2015-04-25 17:20 (:0)

Comments

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