Serial Port Communications

I have a program that I want to dial a number, however when I run the program nothing happens.Please tell me whats wrong with this code.
#include<windows.h>
#include<windowsx.h>
#include<iostream.h>
void main()
{
      DCB *dcb;
char jess[31]="ATDP 169";
char *jesse=jess;
int dummy;
HANDLE hComm;
hComm = CreateFile( "COM2",  
                    GENERIC_READ | GENERIC_WRITE,      
                              0,
                    0,
                              OPEN_EXISTING,
                    FILE_FLAG_WRITE_THROUGH,
                    0);
cout<<"Handle to Com2 opened!\n";
cout<<"Dialing test!\n";
GetCommState(hComm,dcb);
SetCommState(hComm,dcb);
WriteFile(hComm,jesse,strlen(jesse),0,NULL);
cin>>dummy;
CloseHandle(hComm);
cout<<"Closed!";
}
LVL 5
laeuchliAsked:
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galkinConnect With a Mentor Commented:
Lok at documentation of WriteFile. This is extract from there "...If lpOverlapped is NULL, lpNumberOfBytesWritten cannot be NULL...". Forth and the fifth parameters cannot be NULL together.
Besides strlen returns string length EXCLUDING '\0' character so correct string length is strlen() + 1.
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nietodCommented:
Although the rest of your answer is surely right, I'm not sure why you are suggesting there might be a problem with the string length.  There is a problem only if he wants to send the NUL character and this is unlikely.
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stefanrCommented:
How about adding a '\r' to the dial string, i.e.
char jess[31]="ATDP 169\r";

/Stefan
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stefanrCommented:
...and (oops!) change
DCB *dcb;
to
DCB dcb;
and
GetCommState(hComm,dcb);
to
GetCommState(hComm,&dcb);
and similar to SetCommState.
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