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Top Forums Shell Programming and Scripting Understand Bash scripting encryption Post 302236004 by renpippa on Sunday 14th of September 2008 08:00:07 AM
Old 09-14-2008
Question Understand Bash scripting encryption

Dear all,

I have been working with Linux for quite few years but never required to learn Bash and Linux really dep doan.
I want to learn bash I bought books and Have been reading on the Internet but I cannot find my answers, maybe I am blind.

For example:
What does this means?
# for i in Smilie
Where can I find what the "i" and the "in" means and their significance.
I need to nderstand where they come from and where can I find all of them, for example sometimes I see "# while -n blabla" what "-n" mean and where can I find explanations for similar things?

If you guys could give me some light I would be really happy and thankful.

Cheers
 

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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)
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