Message-ID: <000b01c05f60$3ce4ca60$f504883e@gtdf>
From: "Greg Holdridge" <greg AT holdridge7 DOT freeserve DOT co DOT uk>
To: <djgpp AT delorie DOT com>
References: <90j6oj$fjt$1 AT news5 DOT svr DOT pol DOT co DOT uk> <7458-Tue05Dec2000234242+0200-eliz AT is DOT elta DOT co DOT il>
Subject: Re: realloc causing fault
Date: Wed, 6 Dec 2000 08:40:48 -0000
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Reply-To: djgpp AT delorie DOT com

---- Original Message -----
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Greg Holdridge <greg AT holdridge7 DOT freeserve DOT co DOT uk>
Cc: <djgpp AT delorie DOT com>
Sent: Tuesday, December 05, 2000 9:42 PM
Subject: Re: realloc causing fault


> Your calculations are mistaken.  You don't take into account the
> overhead of each allocation (8 bytes per allocated buffer).  So in
> fact you allocate much more than 150KB.  You also do it very

even so, with 64MB plus virtual mem it should be ok.

> inefficiently: allocating memopry 1 byte at a time, then reallocating
> it for the next byte is about the worst memory usage I could think of.

not one byte, one string.  And besides, I need to allocate in array format
because strings are accessed by code.  Otherwise access would be very slow,
if for example I used the binary tree structure I use for compression. How
else could this be achieved without pre-allocation the stringtable space (I
suppose if I put the numstrings in the compressed file header? LZW produces
the same number of strings both ways I guess)

> I could try guessing where your program crashes and why, but I don't
> want to guess.  Please post the full crash message printed by the
> program, after running symify on it, and please show on the source

I cant do this easily since the fault cause is handled by windows under a
DOS-box and so no frame trace is performed - just a little grey window pops
up telling me 'the DOS program was naughty and has been...' However the
references I get are

_malloc +545
_realloc +40

> If you want to understand that, read the source of malloc and realloc
> in djlsr203.zip.  There is a good reason for the address to move up.

Thanks then,
Greg