Reading a string from a ptr, don't work

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DLL Talk / Reading a string from a ptr, don't work

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Posted: 25th Dec 2005 06:41 Edited at: 25th Dec 2005 06:46

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I have some simple but troublesome code
the compiled exe crashes(silent) when i se the read string function but write string is OK

here is my example dbp code

+ Code Snippet

ptr AS DWORD
ptr=make memory(100)
wait key

write string to pointer ptr,"H"
wait key
tmp$=read string from pointer(ptr) `crashes here
`wait key
print tmp$
delete memory ptr
`print t
`close shared memory 1,ptr
wait key

and heres my also very simple code

+ Code Snippet

DWORD dbpstring(LPSTR pstring) //handy little function to return strings, I'm thinking the problem is here
 {
        LPSTR pret=NULL;
       DWORD dwSize=strlen((LPSTR)pstring );
         g_pGlob->CreateDeleteString ( (DWORD*)&pret, dwSize+1 );
         strcpy(pret, (LPSTR)pstring);
         return (DWORD) pret;
}

DWORD ReadString(DWORD ptr){ //reads a string from ptr till a null
	return dbpstring((LPSTR)ptr); //well that was easy
}

thanks in advance

edit:
I'm also thinking that dbp's strings aren't null terminated which would make the crash make sense

I didnt fail, I just found 10,000 ways that don't work
-Thomas Edison

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OSX Using Happy Dude

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Joined: 21st Aug 2003

Location: At home

Posted: 25th Dec 2005 10:35 Edited at: 25th Dec 2005 10:45

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Is read string from pointer(ptr) the function DWORD dbpstring(LPSTR pstring)?
If so, your getting parameter types messed up.

I would do something like :

+ Code Snippet

DWORD dbpstring(DWORD mem,DWORD memSize) 
 {
        LPSTR pret=NULL;
      
         g_pGlob->CreateDeleteString ( (DWORD*)&pret, memSize+1 );
         if (pret)
         {
             strncpy(pret, (LPSTR) mem,min(strlen(memSize),memSize));
         }
         return (DWORD) pret;
}

As were not passing in a previous string, we dont need to worry about deleting it.

DBPro strings are null terminated.

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DLL Talk / Reading a string from a ptr, don't work