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</o:shapelayout></xml><![endif]--></head><body lang=EN-NZ link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>This does work.<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>GetMem(a,10);<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>GetMem(b,10);<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>StrCopy(a,'abcdefghi');<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>StrCopy(b,'jklmnopqr');<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>StrCopy(a,b);<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>I don’t get why this is necessary when a := 'abcdefghi' should do the same thing, but I’ll need to make some changes.<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> delphi-bounces@listserver.123.net.nz [mailto:delphi-bounces@listserver.123.net.nz] <b>On Behalf Of </b>Ross Levis<br><b>Sent:</b> Sunday, 12 May 2013 5:31 PM<br><b>To:</b> 'NZ Borland Developers Group - Delphi List'<br><b>Subject:</b> Re: [DUG] StrCopy problem<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>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.<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'>Ross.<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> <a href="mailto:delphi-bounces@listserver.123.net.nz">delphi-bounces@listserver.123.net.nz</a> [<a href="mailto:delphi-bounces@listserver.123.net.nz">mailto:delphi-bounces@listserver.123.net.nz</a>] <b>On Behalf Of </b>Bevan Edwards<br><b>Sent:</b> Sunday, 12 May 2013 4:48 PM<br><b>To:</b> <a href="mailto:delphi@listserver.123.net.nz">delphi@listserver.123.net.nz</a><br><b>Subject:</b> Re: [DUG] StrCopy problem<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>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?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Have you tried allocating 10 bytes of memory to 'a' and then using StrCopy?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Have you run the debugger and checked where the PChars 'a' and 'b' are pointing to before StrCopy?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div><p class=MsoNormal style='margin-bottom:12.0pt'><br><br><br>-------- Original message --------<br>From: Ross Levis <<a href="mailto:ross@stationplaylist.com">ross@stationplaylist.com</a>> <br>Date: <br>To: 'NZ Borland Developers Group - Delphi List' <<a href="mailto:delphi@listserver.123.net.nz">delphi@listserver.123.net.nz</a>> <br>Subject: Re: [DUG] StrCopy problem <o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>Doesn’t really help.<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>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.<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>Ross.<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> <o:p></o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:#1F497D'> <a href="mailto:delphi-bounces@listserver.123.net.nz">delphi-bounces@listserver.123.net.nz</a> [<a href="mailto:delphi-bounces@listserver.123.net.nz">mailto:delphi-bounces@listserver.123.net.nz</a>] <b>On Behalf Of </b>Keith Allpress<br><b>Sent:</b> Sunday, 12 May 2013 10:27 AM<br><b>To:</b> 'NZ Borland Developers Group - Delphi List'<br><b>Subject:</b> Re: [DUG] StrCopy problem</span><span style='color:#1F497D'><o:p></o:p></span></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>Perhaps:<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'><a href="http://rvelthuis.de/articles/articles-pchars.html">http://rvelthuis.de/articles/articles-pchars.html</a><o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> <o:p></o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-US style='color:#1F497D'>From:</span></b><span lang=EN-US style='color:#1F497D'> <a href="mailto:delphi-bounces@listserver.123.net.nz">delphi-bounces@listserver.123.net.nz</a> [<a href="mailto:delphi-bounces@listserver.123.net.nz">mailto:delphi-bounces@listserver.123.net.nz</a>] <b>On Behalf Of </b>Ross Levis<br><b>Sent:</b> Sunday, 12 May 2013 2:39 a.m.<br><b>To:</b> 'NZ Borland Developers Group - Delphi List'<br><b>Subject:</b> [DUG] StrCopy problem</span><span style='color:#1F497D'><o:p></o:p></span></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>var<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> a: pChar;<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> b: pChar;<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>begin<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> a := 'abcdefghi';<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> b := 'jklmnopqr';<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> StrCopy(a,b);<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>end;<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'>Question: Why does this code crash?<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='color:#1F497D'> <o:p></o:p></span></p></div></div></div></body></html>