From: "Michael Beck" <beck AT dresearch DOT de>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: division after for loop
Date: Sun, 7 Mar 1999 01:27:52 +0100
Organization: DResearch
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Message-ID: <7bsh1u$cgd$1@latinum.dresearch.de>
References: <36E1B306 DOT 176F24E4 AT usa DOT net>
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To: djgpp AT delorie DOT com
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Victor Senderov wrote in message <36E1B306 DOT 176F24E4 AT usa DOT net>...
>The following is a part of a program I was trying to write. The problem
>is that
>if the for loop is used flPart will be incorect. If it is cut everything
>works just
>fine.
...

>    char* stgClean = "\0";

Here, you are defining a pointer, intitialy point to some location holding a
'\0'.

>    int j = 0;
>// THIS LOOP CAUSES
>    for (int i = 0; stg[i] != '\0'; i++)
>   {
>     if (stg[i] >= '0' && stg[i] <= '9' || stg[i] == '.') stgClean[j]
=stg[i];

Now here, you overwrite this location. Even worser, if j gets bigger than 0,
you start overwriting
the data behind this location. Doing this kind you can easyly overwrite
whatever data you want.
If your flPart is a global defined variable, its address may be just some
bytes behind the first '\0', so
it gets overwritten! You must allocate an array of chars, not a char
pointer. Change it to

char stgClean[SOME_CONSTANT];

Than your program will work if j NEVER gets bigger than SOME_CONSTANT-1.
However, best
solution is to remove the temporal buffer stgClean completely...

--
Michael Beck,                   email: beck AT dresearch DOT de