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From: zhou@brazil.psych.purdue.edu (Albert Zhou)
Newsgroups: comp.lang.pascal
Subject: Re: Patching a process in prompt
Message-ID: <11684@j.cc.purdue.edu>
Date: 14 Jan 91 21:06:10 GMT
References: <25493@adm.brl.mil>
Sender: news@j.cc.purdue.edu
Reply-To: zhou@brazil.psych.purdue.edu (Albert Zhou)
Organization: Purdue University
Lines: 21

In article <25493@adm.brl.mil> ZCCBJSB%EB0UB011.BITNET@cunyvm.cuny.edu (Josep Sau B.) writes:
>
>Has anyone any idea/code to achieve that every time system
>PROMPT appears a program gets called before?
>
It is possible to do this. However, it would be very slow since each time the
program has to be loaded from the disk and executed. But anyway, you can do
that with TP4.0 and up by writing your own shell (very easy, since you can     
make full use of the existing command interpreter). The code will be something
like this:

		repeat
		  execute you pre-prompt program 
                        (like this: exec(program, parameters);		
		  write prompt;	
		  read a command line;
		  decide whether it is an internal command or an external one
		  if it is an internal command then
		     use this form: exec('command.comm`, `/c ` + commandline)
		  else use this form: exec(command, parameters);
		until whatever;