Understanding awk 'expansion' Post: 302959235

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pam_localuser

PAM_LOCALUSER(8)						 Linux-PAM Manual						  PAM_LOCALUSER(8)

NAME

       pam_localuser - require users to be listed in /etc/passwd

SYNOPSIS

       pam_localuser.so [debug] [file=/path/passwd]

DESCRIPTION

       pam_localuser is a PAM module to help implementing site-wide login policies, where they typically include a subset of the network's users
       and a few accounts that are local to a particular workstation. Using pam_localuser and pam_wheel or pam_listfile is an effective way to
       restrict access to either local users and/or a subset of the network's users.

       This could also be implemented using pam_listfile.so and a very short awk script invoked by cron, but it's common enough to have been
       separated out.

OPTIONS

       debug
	   Print debug information.

       file=/path/passwd
	   Use a file other than /etc/passwd.

MODULE TYPES PROVIDED

       All module types (account, auth, password and session) are provided.

RETURN VALUES

       PAM_SUCCESS
	   The new localuser was set successfully.

       PAM_SERVICE_ERR
	   No username was given.

       PAM_USER_UNKNOWN
	   User not known.

EXAMPLES

       Add the following line to /etc/pam.d/su to allow only local users in group wheel to use su.

	   account sufficient pam_localuser.so
	   account required pam_wheel.so

FILES

       /etc/passwd
	   Local user account information.

SEE ALSO

       pam.conf(5), pam.d(5), pam(7)

AUTHOR

       pam_localuser was written by Nalin Dahyabhai <nalin@redhat.com>.

Linux-PAM Manual						    06/04/2011							  PAM_LOCALUSER(8)