Fantastic. I had it a bit mixed up so this is a much better explanation. How about this one?
sed - live stream editor. Can replace multiple occurrences of text simultaneously.
-i - in-place argument. When combined with sed it replaces text and overwrites the original.
-i.bak - when using the extension .bak at the end of -i this allows you to keep a copy of the old file under that extension.
13iwww - specifies the 13th line on where to insert the sed replacement
IN - declares you are replacing
CNAME -
Lanstic.com. - in the quoted text it is the text being searched and replaced
This command uses the “sed” stream editor to replace a line of text with another. In this case it is looking for the 13th line in a file and replacing the CNAME of it wit lantstic.com. It should first create the backup (-i.bak) to /var/named/lanstic.com.db.tmp and if it is successful will mv (move) the old var/named/lanstic.com.db.tmp and replace it with the new var/named/lanstic.com.db
As I suggested before, PLEASE stop trying to guess what these commands do and type them into your keyboard and see how they behave instead. Then, if you don't understand what happened, open up a new thread with the command that isn't working the way you think it should. Trying to keep track of multiple questions in a single thread confuses people who are trying to help you.
For the case above, the sed editing command is 13i (not 13iwww) and it tells sed to insert text before line 13. With a GNU sed on a Linux system, the text to be inserted will be:
And, the file being edited is /var/named/lanstic.com.db. Do note that the pathnames with and without the leading slash character are very different unless you are sitting in your system's root directory when you invoke that sed command.
Hi,
I am trying talk but it isn't working.
I tried
talk ip terminal
talk ip:terminal
First it says:
Then after 2 seconds
I have checked the mesg status: Its y
I am not getting any invitation on the other machine.
Thanks in Advance (1 Reply)
I have the manpage for this utility on my system, but the utility itself is not there.
My friend has the utility, but it does not work, not even on the same machine.
Does anyone remember it? What software package is it related to? Where is it configured? (1 Reply)
Hi,
Could you please advice on the following query:
There are 2 users on a unix box:
1. aaaa
2. bbbb
I open 2 putty sessions and login with the above 2 users.
Then I type the following using the aaaa user to chat with bbbb.
talk bbbb
or
talk bbbb@hostname
Result: the screen goes... (1 Reply)
using talk option i tried to send message to my team mate.
for connecting to one unix box, we are having a common userid and password
except that, the ip addresses will change
for me it is x.x.x.4, for my colleague it is x.x.x.3
These are the steps i did
> who
<userid> pts/2 ... (1 Reply)
Hi! I would like to start creating a bridge for good old Unix talk program. This bridge would allow you to joinIRC-channel by using talk just for example. I have a couple of questions:
1. Are there any previous attempts or implementations creating Talk bridge?
2. Which version of the talk... (9 Replies)
Discussion started by: homebeach
9 Replies
LEARN ABOUT BSD
learn
LEARN(1) General Commands Manual LEARN(1)NAME
learn - computer aided instruction about UNIX
SYNOPSIS
learn [ -directory ] [ subject [ lesson ] ]
DESCRIPTION
Learn gives Computer Aided Instruction courses and practice in the use of UNIX, the C Shell, and the Berkeley text editors. To get started
simply type learn. If you had used learn before and left your last session without completing a subject, the program will use information
in $HOME/.learnrc to start you up in the same place you left off. Your first time through, learn will ask questions to find out what you
want to do. Some questions may be bypassed by naming a subject, and more yet by naming a lesson. You may enter the lesson as a number
that learn gave you in a previous session. If you do not know the lesson number, you may enter the lesson as a word, and learn will look
for the first lesson containing it. If the lesson is `-', learn prompts for each lesson; this is useful for debugging.
The subject's presently handled are
files
editor
vi
morefiles
macros
eqn
C
There are a few special commands. The command `bye' terminates a learn session and `where' tells you of your progress, with `where m'
telling you more. The command `again' re-displays the text of the lesson and `again lesson' lets you review lesson. There is no way for
learn to tell you the answers it expects in English, however, the command `hint' prints the last part of the lesson script used to evaluate
a response, while `hint m' prints the whole lesson script. This is useful for debugging lessons and might possibly give you an idea about
what it expects.
The -directory option allows one to exercise a script in a nonstandard place.
FILES
/usr/share/learn subtree for all dependent directories and files
/usr/tmp/pl* playpen directories
$HOME/.learnrc startup information
SEE ALSO csh(1), ex(1)
B. W. Kernighan and M. E. Lesk, LEARN - Computer-Aided Instruction on UNIX
BUGS
The main strength of learn, that it asks the student to use the real UNIX, also makes possible baffling mistakes. It is helpful, espe-
cially for nonprogrammers, to have a UNIX initiate near at hand during the first sessions.
Occasionally lessons are incorrect, sometimes because the local version of a command operates in a non-standard way. Occasionally a lesson
script does not recognize all the different correct responses, in which case the `hint' command may be useful. Such lessons may be skipped
with the `skip' command, but it takes some sophistication to recognize the situation.
To find a lesson given as a word, learn does a simple fgrep(1) through the lessons. It is unclear whether this sort of subject indexing is
better than none.
Spawning a new shell is required for each of many user and internal functions.
The `vi' lessons are provided separately from the others. To use them see your system administrator.
7th Edition October 22, 1996 LEARN(1)