Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!apple!usc!ucla-cs!uci-ics!milne
From: milne@ics.uci.edu (Alastair Milne)
Newsgroups: comp.lang.pascal
Subject: Re^2: Standard Pascal
Message-ID: <18965@paris.ics.uci.edu>
Date: 1 Jul 89 01:04:48 GMT
References: <8616@pyr.gatech.EDU>
Sender: news@paris.ics.uci.edu
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mlw@pyr.gatech.EDU (Michael Williams) writes:
>Borland obviously left get and put out of turbo pascal for a reason.
>Can anyone tell me why get and put are better than read and write?
>Used in conjunction with the seek command, I find read/write almost
>identical to array access for a file of records, which is quite helpful.

   I suspect the reason was nothing more profound than a desire to simplify the
   parse tables -- and the number of predeclared routines.  (Though there is
   perhaps a more substantial reason: they haven't implemented file variables
   as pointers to the file window, which is what -- or close to what -- most
   Pascal's do.  See below about the consequences of not doing so.)

   I don't know that GET and PUT are necessarily "better" than read or write,
   but they are certainly more standard.  Using them, I can transport typed
   file I/O among a number of Pascal dialects; Turbo is the only one I know of
   that overloads READ and WRITE, so it's the only one where that will work.  

   I can't see any real advantage in SEEK and READ, rather than SEEK and GET:

       SEEK( RecordFile, RecordIndex);
       READ( RecordFile, NewRecord);

       or

       SEEK( RecordFile, RecordIndex);
       GET( RecordFile);
       NewRecord := RecordFile^;  { In Turbo, this assignment is impossible,
				    because the file variable isn't a window
				    pointer, so it can't be dereferenced. }

   As far as I'm aware, the principal impact of this substitution is that
   porting things between Turbo and other dialects gets a little harder.


   Alastair Milne