I have the following but getting compile errors...

Code:
void xboard(pcon)
{
for (;;) {
if (side == computer)
{
DWORD Id;
CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)think, pcon, 0, &Id);
...
}
...
...
}

void think(PVOID pArg)
{
PCON pcon = (PCON)pArg;
.....
.....
}
Inside my header file where I define all my functions, I have,
Code:
void think(PVOID pArg);
The errors I am getting are...

c:\documents and settings\gopi\desktop\chesscalc\protos.h(14) : error C2146: syntax error : missing ')' before identifier 'pArg'
c:\documents and settings\gopi\desktop\chesscalc\protos.h(14) : error C2061: syntax error : identifier 'pArg'
c:\documents and settings\gopi\desktop\chesscalc\protos.h(14) : error C2059: syntax error : ';'
c:\documents and settings\gopi\desktop\chesscalc\protos.h(14) : error C2059: syntax error : ')'
c:\documents and settings\gopi\desktop\chesscalc\chesscalc.c(53) : error C2065: 'think' : undeclared identifier
c:\documents and settings\gopi\desktop\chesscalc\search.c(133) : error C2198: 'ExitThread' : too few actual parameters

Ofcourse I am having #include <Windows.h> in files having xboard() and think() functions..
So please help me. Thanks.