NetNews Usenet Archive 1992 #18/NN_1992_18.iso/spool/comp/sys/mac/programm/13954

Internet Message Format | 1992-08-13 | 1.8 KB

Path: sparky!uunet!elroy.jpl.nasa.gov!swrinde!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!scasterg
From: [e-mail] (Stuart M Castergine)
Newsgroups: comp.sys.mac.programmer
Subject: Newsbie needs help. Getting data out of buffPtr
Summary: pointers types conversions buffers confusion
Message-ID: <[e-mail]>
Date: 13 Aug 92 19:15:02 GMT
Sender: [e-mail]
Organization: The Ohio State University
Lines: 32
Nntp-Posting-Host: bottom.magnus.acs.ohio-state.edu


I'm very new at both C and Macintosh programming, so bear with me. My
first project is a Hypercard XFCN. Very simple to start with.

1. Path to a file is passed in as a parameter
2. Open File
3. Read some data from file.
4. Do some stuff with the data.
5. Write data to an output file.
6. Pass back the pathname of the output file to Hypercard.

Now, since I'm so new. Everything is difficult. I've got everything
down up through step 3. the data is read in, it's in the buffer
buffPtr (type Ptr).

My question is:

1. How do I get the data out of buffPtr and into a string or array of
char or whatever where I can look at it and work with it?  I'll
essentially be breaking the data into different chunks, writing some
to the output file, calculating numbers using some of the bits as lsb
and msb of the numbers I want and writing them to the output file and
repeating this for blocks of data read in from the input file until EOF.

I think I can handle the manipulation once I get the data somewhere
where I know how to work with it, but I'm having trouble with the
incompatible pointer types and other things I don't understand.

--
[e-mail] -- Stuart M. Castergine
Fiver: "Oh, Hazel, look! The field! It's covered with blood!"
Hazel: "Don't be silly, it's only the light of the sunset." -- Watership Down