Basic Linux command line question Post: 302993066

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Top Forums UNIX for Beginners Questions & Answers Basic Linux command line question Post 302993066 by drysdalk on Monday 6th of March 2017 12:19:17 PM

03-06-2017

Registered User

Hi,

OK, there are various things going here that perhaps need explaining. About the simplest way I can think of tackling your questions is to start with explaining what each of these commands actually does, which might help you understand what you're seeing a bit better.

pwd
This command will print out what's called your current working directory. Your working directory is the directory in the filesystem that you're in at the moment. You change directories with the..

cd
command. cd changes directories, and nothing else. So it's the command you use to change your working directory, and navigate around the filesystem.

su
The switch user command. Nearly always used as a regular user to switch to assume the permissions of the root user. root is the super-user account - that is, the account on a UNIX system that (usually) has full access to all directories and parts of the system, and has permission to run all commands.

Next, I think it would be helpful for you to realise there's a clear distinction between users and directories. Broadly speaking, every user on a UNIX system has one directory on the system reserved for their own use, called their home directory. Typing cd on its own will take you back to this home directory in almost all circumstances. But this home directory needn't have the same name as the user, and can be anything at all. Likewise, any directory on the system can take any name. Every directory on the filesystem will be owned by one particular user and one particular group.

Now, when you use su, the default behaviour will be to leave you in whatever directory you happen to be in at the time, rather than to switch you to the home directory of the user you're wanting to become. If you want it to do that (and more besides), try using the syntax su - instead. This will execute the full login environment of the user you're switching to, and so you will find your current working directory will change to their home directory.

Anyway, hope all this helps you to understand a bit more clearly what's going on here.

drysdalk

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LEARN ABOUT SUNOS

userdel

userdel(1M)						  System Administration Commands					       userdel(1M)

NAME

       userdel - delete a user's login from the system

SYNOPSIS

       userdel [-r] login

DESCRIPTION

       The  userdel  utility  deletes a user account from the system and makes the appropriate account-related changes to the system file and file
       system.

OPTIONS

       The following options are supported:

       -r	Remove the user's home directory from the system. This directory must exist. The files and directories under  the  home  directory
		will no longer be accessible following successful execution of the command.

OPERANDS

       The following operands are supported:

       login	An existing login name to be deleted.

EXIT STATUS

       The following exit values are returned:

       0	Successful completion.

       2	Invalid command syntax. A usage message for the userdel command is displayed.

       6	The account to be removed does not exist.

       8	The account to be removed is in use.

       10	Cannot update the /etc/group or /etc/user_attr file but the login is removed from the /etc/passwd file.

       12	Cannot remove or otherwise modify the home directory.

FILES

       /etc/passwd	       system password file

       /etc/shadow	       system file contain users' encrypted passwords and related information

       /etc/group	       system file containing group definitions

       /etc/user_attr	       system file containing additional user attributes

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       auths(1),  passwd(1),  profiles(1),  roles(1),  users(1B),  groupadd(1M), groupdel(1M), groupmod(1M), logins(1M), roleadd(1M), rolemod(1M),
       useradd(1M), userdel(1M), usermod(1M), passwd(4), prof_attr(4), user_attr(4), attributes(5)

NOTES

       The userdel utility only deletes an account definition that is in the local /etc/group, /etc/passwd, /etc/shadow, and /etc/user_attr  file.
       file. If a network name service such as NIS or NIS+ is being used to supplement the local /etc/passwd file with additional entries, userdel
       cannot change information supplied by the network name service.

SunOS 5.10							    8 Sep 1999							       userdel(1M)