[DUG] StrCopy problem

[Ross Levis]

I did see a & b had a pointer address allocated.  It looked like a normal pointer address range.  I’ll try allocating 10 bytes to a later and see what happens.

 

Ross.

 

From: delphi-bounces at listserver.123.net.nz [mailto:delphi-bounces at listserver.123.net.nz] On Behalf Of Bevan Edwards
Sent: Sunday, 12 May 2013 4:48 PM
To: delphi at listserver.123.net.nz
Subject: Re: [DUG] StrCopy problem

 

Actually, based on that article a:='abcdefghi' should assign 10 bytes and include the zero byte at the end. But I wonder if the problem is due to where this data is stored and trying to copy b to a results in an attempt to write to protected memory?

 

Have you tried allocating 10 bytes of memory to 'a' and then using StrCopy?

 

Have you run the debugger and checked where the PChars 'a' and 'b' are pointing to before StrCopy?

 




-------- Original message --------
From: Ross Levis <ross at stationplaylist.com> 
Date: 
To: 'NZ Borland Developers Group - Delphi List' <delphi at listserver.123.net.nz> 
Subject: Re: [DUG] StrCopy problem 



Doesn’t really help.

 

a := 'abcdefghi' does allocate 9 bytes of RAM.  I can access a and b after it is assigned.  The problem is StrCopy crashes.  I would expect “a” to have the same string as b once this is executed.

 

Ross.

 

From: delphi-bounces at listserver.123.net.nz [mailto:delphi-bounces at listserver.123.net.nz] On Behalf Of Keith Allpress
Sent: Sunday, 12 May 2013 10:27 AM
To: 'NZ Borland Developers Group - Delphi List'
Subject: Re: [DUG] StrCopy problem

 

Perhaps:

http://rvelthuis.de/articles/articles-pchars.html

 

 

From: delphi-bounces at listserver.123.net.nz [mailto:delphi-bounces at listserver.123.net.nz] On Behalf Of Ross Levis
Sent: Sunday, 12 May 2013 2:39 a.m.
To: 'NZ Borland Developers Group - Delphi List'
Subject: [DUG] StrCopy problem

 

var

  a: pChar;

  b: pChar;

begin

  a := 'abcdefghi';

  b := 'jklmnopqr';

  StrCopy(a,b);

end;

 

Question:  Why does this code crash?

 

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