bash script for showing last users Post: 302365597

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Top Forums Shell Programming and Scripting bash script for showing last users Post 302365597 by methyl on Tuesday 27th of October 2009 01:50:32 PM

10-27-2009

Registered User

It is probably easier to work with the raw wtmp file than with "last" if only because "last" is always in reverse chronological order.
I'm assuming that you want to do this in shell rather than a "C".

The fact that you can process an entire "output from "last" suggests that you properly maintain your wtmp file(s) to a manageable size.

Tip: process the wtmp file with program "fwtmp" and you will have all the raw material in chronological order in a format suitable for splitting into fields with "cut". Each record includes the date since the epoch as well as in character format. Each record contains a code as to the type of record. Beware that some records don't have a username because "wtmp" records that fact that someone is running a login process (hence the reason to use "cut").

There are many possible ways to deal with the timespan. You could run "fwtmp" at the start of the period and again at the end of the period. Count the records in each file and you then know how many have changed. Use "sed" not "tail" to get the records you require. At this point you could convert the selected records back to wtmp format in a file with a new name and run "last" on that file.

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installsieve

INSTALLSIEVE(1) 					      General Commands Manual						   INSTALLSIEVE(1)

 *

NAME

       installsieve - user utility for managing sieve scripts

SYNOPSIS

       installsieve

DESCRIPTION

       installsieve is a utility that allows users to manage their sieve scripts kept on the server.

OPTIONS

       -v <name> View script with the given name. The script if retrieved sucessfully is output to standard output.

       -l  List  all  of  the scripts currently on the server. If one of the scripts is active a arrow is printed indicating that it is the active
       script.

       -p <port> Port to connect to. If left off this defaults to "sieve" as defined in /etc/services.

       -i <file> Install a file onto the server. If a script with the same name already exists on the server it is overwritten.  Upon  sucessfully
       putting	the  script on the server the script is set active. If <file> has the extension .script it is chopped when put on the server since
       sieve names may not contain a '.'.

       -a <name> Set <name> as the active script. The list of available names can be obtained from the '-l' option..

       -d <name> Delete the sieve script on the server with <name>.

       -m <mechanism> Force installsieve to use <mechanism> for authentication. If not specified the strongest authentication mechanism is chosen.

       -g <name> Get the sieve script with <name> and save it to disk with a ".script" extension. If a file with that name already  exists  it	is
       overwritten.

       -u <user> Userid/Authname to use for authentication; by default, the current user.

CMU
								   Project Cyrus						   INSTALLSIEVE(1)