Date:	Thu, 21 Aug 1997 16:49:56 -0200
Message-Id:	<199708211849.QAA001.21@ns1.bspu.ac.by>
To:	DJGPP mailing list <djgpp AT delorie DOT com>
From:	Alexander Bokovoy <bokovoy AT bspu DOT ac DOT by>
Subject:	SIGSEGV or SIGABRT during execution
MIME-Version:	1.0

Could somebody explain what is wrong in the next piece of code
which is successfully compiled from RHIDE but during execution
breaks with SIGSEGV (if execute from DOS) or SIGABRT (from RHIDE).
Debugging shows that error occures in the next line:

     KeyWord=new char[strlen(keyword)]; // Create and fill key field

in the HTNode constructor.
There are declaration part, 
constructor implementation and stderr output:
-------------------------------------------------------------

       // HTNode declaration
class HTNode {
public:
   char *KeyWord;      // Title of topic/link
   long Seek;          // For topic: offset in the file
   int  Size;          // Size in lines
   int  Appears;       // Number of line where appears title
                       //
   HTNode *NextTopic;  // Next topic in the list
   HTNode *PrevTopic;  // Previous topic in the list
   HTNode *Reference;  // Next link in the list
   int  X,Y;           // Position in the text
                       // (used only by interpreter)
      // Constructor
      HTNode(char *keyword, long seek, int size, int appears, int=0, int=0);
      ~HTNode();      // Destructor
   // Redefine operators
   friend int operator > (HTNode &a, HTNode &b); // Compare by
   friend int operator < (HTNode &a, HTNode &b); // KeyWord
   friend int operator > (char *a, HTNode &b);   // Compare KeyWord with
   friend int operator < (char *a, HTNode &b);   // string
};
------------------------------------------------------------------
// HTNode constructor
HTNode::HTNode(char *keyword, long seek, int size, int appears, int x, int y)
{
   NextTopic=PrevTopic=NULL;  // Upper level objects set this pointers
   Reference=NULL;            //
   KeyWord=NULL;
   if(keyword)
   {
     // The next line caused SIGABRT when create second node 
     // (with first - all is OK) from RHIDE and 
     // caused SIGSEGV from DOS in similar situation
     // 
     KeyWord=new char[strlen(keyword)]; // Create and fill key field
     strcpy(KeyWord,strupr(keyword));
   }
   Seek=seek;  Size=size;      // Filling other
   Appears=appears; X=x; Y=y;  // fields
}
//...
-----------------------------------------------------------------
Exiting due to signal SIGSEGV
General Protection Fault at eip=00005310
eax=0000000c ebx=00000001 ecx=fffffffc edx=742f7070 esi=00000006 edi=00053d63
ebp=00053cb8 esp=00053cb0 program=C:\LANGS\HYPERT~1\HTMAKE.EXE
cs: sel=00f7  base=82b4d000  limit=0006ffff
ds: sel=00ff  base=82b4d000  limit=0006ffff
es: sel=00ff  base=82b4d000  limit=0006ffff
fs: sel=00d7  base=0001c350  limit=0000ffff
gs: sel=010f  base=00000000  limit=ffffffff
ss: sel=00ff  base=82b4d000  limit=0006ffff

Call frame traceback EIPs:
  0x00005310
  0x000039c4
  0x0000397f
  0x00002a36
  0x000027ff
  0x00002442
  0x00002693
  0x00003f7e
----------------------------------------------------------------
Alexander Bokovoy, <bokovoy AT bspu DOT ac DOT by>
---== The Soft Age coming soon ==---

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