Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!ux1.lbl.gov!beard
From: beard@ux1.lbl.gov (Patrick C Beard)
Newsgroups: comp.sys.mac.programmer
Subject: Re: LSC 3.0 scanf deletes
Summary: Don't use scanf!!!
Keywords: delete, scanf
Message-ID: <587@helios.ee.lbl.gov>
Date: 2 Aug 88 22:23:22 GMT
References: <2559@pt.cs.cmu.edu>
Sender: usenet@helios.ee.lbl.gov
Reply-To: beard@ux1.lbl.gov (Patrick C Beard)
Organization: Lawrence Berkeley Laboratory, Berkeley
Lines: 44

In article <2559@pt.cs.cmu.edu> phd@speech1.cs.cmu.edu (Paul Dietz) writes:
>I'm tired of fighting this one. Does anybody know how to delete
>characters when you make a mistake typing during an LSC scanf?
>Any suggestions would be appreciated. Thanks!
>
>Paul H. Dietz                                        ____          ____

The answer to your question is, DON'T USE SCANF!  I have always hated
the way scanf treats the user who assumes he can edit his command line.
A better approach to getting lines of input and parsing them from the user
is to use gets() and then sscanf().  For example:

Instead of:

float foo()
{
	float in_value;

	printf("enter a floating point value:  ");
	scanf("%f",&in_value);	/* yuck, user can't edit his input! */
	return(in_value);
}

use:

float foo()
{
	float in_value;
	char buf[80];	/* overconservative */

	printf("enter ... ");
	gets(buf);	/* user can use backspace to edit */
	sscanf(buf,"%f",&in_value);
	return(in_value);
}

I hope this helps.

+=============================================================+
|                    Patrick C. Beard                         |
|              Lawrence Berkeley Laboratory                   |
|               Automated Supernova Search                    |
+-------------------------------------------------------------+
|              PCBeard@LBL.gov (arpa only)                    |
+=============================================================+