🚀 go-pugleaf

I would like to know how to solve the following problem:

    basically to implement something like pipeline ( | ) in unix 
    terminology; I want to transform every input character typed 
    from the keyboard into another predefined character which will
    become an input character to, for example, MacWrite
    (for example, if you type ABC, it might be transformed into 1GK
    which will then be fed to MacWrite).
    
    When I use MacWrite, all the characters typed from the keyboard
    will be input to MacWrite DIRECTLY.  What I saw was that, after
    activating MacWrite, I activate some special Desk Accessory program
    (THIS IS WHAT I WANT TO IMPLEMENT)  which
    TRANSFORMS every input character into another predefined character
    which is then fed to MacWrite.
    The D/A seemd to have capability to check whether Capital-Lock key was
    locked, Command key was pressed, and Option key was pressed.


You may safely assume that I know how to implement transforming procedure;
what I am eager to know is :
    0) which programming language can be used (basic, pascal, etc.) and
       if some specific language MUST be used to write a D/A,
    1) how to write a code to read the input character from the keyboard
       within a D/A,
    2) how to check whether Capital-Lock key/Command key/Option key was
       pressed,
    3) how to make the transformed character fed to MacWrite,
    4) what Mac manuals/documents will give useful information, and
    5) (hopefully) some sample code.

I will appreciate any comments concerning this problem. 
Thanks in advance.  Please reply by e-mail.

                            Kyongsok KIM

                            Department of Computer Science
			    University of Illinois at Urbana-Champaign
			    
my addresses are as follows:

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        -------		-------
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        csnet		kkim@uiuc.csnet,
      			kkim%uiuc@csnet-relay.arpa (obsolete), OR
		        kkim%uiuc.csnet@csnet-relay.arpa (obsolete)

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