That is all fine and good. Yes, you did nothing wrong, but others (who posted full solutions) did - still, this is not your fault, but your request in post #6 could be understood as actively asking for such a solution.

But let bygones be bygones and let us start over. Every UNIX-system has an online help for every command. If you do not know about how to use command "foo", then issue the command

Code:

man foo

at the command line to get help about "foo". "man" is short for "manual" and the format of every page is always the same, so you can't start too early to get acquainted with these pages. You can even enter

Code:

man man

to get a a help article about how to use the "man" utility, how the different chapters are organized, etc..

When i told you that "sed" might be worth looking at, we didn't expect you to know what "sed" does. We expected you to research it, first by looking at the man page ("man sed"), then maybe by searching on the internet (enter "man" "sed" or "sed tutorial" in google and you will find lots of hits - others were in your position too).

Unix is a system which - unlike other systems - requires your active work to accomplish anything worthwhile. It is a very well filled toolbox with very specialised, very small precision tools. Put them together in a good way and you can work wonders. Wait for something to happen and you can wait forever. You can use Windows without every getting in touch with filesystems, networks, processes, memory, or anything. In Unix there is no way around that, but once you can do what you want you can do it on virtually any other system too. Instead of knowing where to click you have to understand what you are doing and once you understand what you do you can use that understanding on any other systems. With Windows you may understand what you do, with Unix you have to.

Another thing about Unix is: all the tools are very small - they are doing only one thing, usually, but do this one thing very good. There are no "integrated self-learning 3D-enabled object-oriented web-centric database oriented" whatnots. It is more like an orchestra - with you as the conductor. Violins are sweet-sounding, but make poor basses, while bassons are great basses but lack the lyric quality of the clarinet ...

There is no such thing as a "basic text filter", as you wrote. At least not in the sense of "basic" in contrast to "advanced" - there is only one specialist and another specialist and whilst the specialist excels in its speciality for everything else it is usually a poor tool (if it works at all). You may need the triangle player only one time in a concert, but try to replace him by anything else you will take away from the experience.

So, be a good conductor and learn not only how the tools are used but also how they are intended to be used and what their "area of expertise" is. Your orchestra will sound all the better.

I hope this helps.

bakunin

PS: Once you have a working sed- (or any other) command, post it. We are open to discussion.

PS: another addendum: you might think that using man pages is for beginners. Dead wrong! they are as much a reference as they are a learning tool and all of us Unixers use them on a daily basis. I cannot work a day in office without looking less than ten times at some man page or other.