Path: utzoo!attcan!uunet!cs.utexas.edu!yale!cs.yale.edu!spolsky-joel
From: spolsky-joel@CS.YALE.EDU (Joel Spolsky)
Newsgroups: comp.sys.ibm.pc.programmer
Subject: int24.c - intercept ugly Abort Retry Ignore prompts
Message-ID: <19736@cs.yale.edu>
Date: 21 Mar 90 20:37:24 GMT
Sender: news@cs.yale.edu
Reply-To: spolsky-joel@CS.YALE.EDU (Joel Spolsky)
Organization: Yale University Computer Science Dept, New Haven CT  06520-2158
Lines: 135

Hi!

Enclosed, uuencoded, please find int24.c. It is a routine I wrote to
trap interrupt 24 and provide a slightly more user-friendly error
message than DOS's usual "Abort, Retry, Ignore...". I thought I'd post
it here in case anyone found it useful. 

To use this, just call install_24() at the beginning of your program
and uninstall_24() at the end. If there is a disk error the interrupt
will pop up a slightly more friendly message, let the user choose a
course of action, and restore the screen. The two most common errors,
namely, write-protection and no disk in drive, generate more
meaningful error messages than weird errors.

This is in Turbo-C. I had to uuencode it because I used some
extended line drawing characters for the pop-up box. It's probably
easily portable to other compilers. It works with DOS 2.X and up
although you should know that DOS 2.X didn't allow "fail" so under 2.X
that option won't pop up. (I don't have DOS 2 so I couldn't test that).

Please let me know if you find bugs, have comments, etc. Also if you
port this to another compiler, please send me the port so I can
incorporate it.

+----------------+----------------------------------------------------------+
|  Joel Spolsky  | bitnet: spolsky@yalecs.bitnet     uucp: ...!yale!spolsky |
|                | internet: spolsky@cs.yale.edu     voicenet: 203-436-1538 |
+----------------+----------------------------------------------------------+
                                                      #include <disclaimer.h>



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end