为什么会编译出错？

[jonslover]

下面这段程序为什么会编译出错啊？
#define WIN32_LEAN_AND_MEAN
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include <time.h>
//#include "MtVerify.h"
//#include <assert.h>


//DWORD ThreadFunc(LPVOID);
DWORD WINAPI ThreadFunc(LPVOID n)
{
int i;
int inside=0;
double val;

srand((unsigned)time(NULL));

for(i=0;i<1000000;i++)
{
double x=(double)(rand())/RAND_MAX;
double y=(double)(rand())/RAND_MAX;

if((x*x+y*y)<=1.0)
inside++;

}
val=(double)inside / i ;
printf("PI=%.4g\n",val*4);

return 0;

}


int main(void)
{
HANDLE hThrd;
DWORD exitcode=0;
DWORD threadId;
DWORD begin;
DWORD elapsed;

puts("Timing normal function call...");
begin=GetTickCount();
ThreadFunc(0);
elapsed=GetTickCount()-begin;
printf("function call took: %d.%.03d seconds\n\n",
elapsed/1000,elapsed%1000);


puts("Time thread+ busy loop...");
begin=GetTickCount();
hThrd=CreateThread(NULL,0,ThreadFunc,(LPVOID)1,0,&threadId);

for(;;)
{
GetExitCodeThread(hThrd,&exitcode);
if(exitcode!=STILL_ACTIVE)
break;
//this chews up lots of cpu times
}

elapsed=GetTickCount()-begin;
printf("Thread + busy loop took: %d.%.03d seconds\n",
elapsed/1000,elapsed%1000);
CloseHandle(hThrd);

return EXIT_SUCCESS;

}

[jonslover]

下面这段程序为什么会编译出错啊？
#define WIN32_LEAN_AND_MEAN
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include <time.h>
//#include "MtVerify.h"
//#include <assert.h>


//DWORD ThreadFunc(LPVOID);
DWORD WINAPI ThreadFunc(LPVOID n)
{
int i;
int inside=0;
double val;

srand((unsigned)time(NULL));

for(i=0;i<1000000;i++)
{
double x=(double)(rand())/RAND_MAX;
double y=(double)(rand())/RAND_MAX;

if((x*x+y*y)<=1.0)
inside++;

}
val=(double)inside / i ;
printf("PI=%.4g\n",val*4);

return 0;

}


int main(void)
{
HANDLE hThrd;
DWORD exitcode=0;
DWORD threadId;
DWORD begin;
DWORD elapsed;

puts("Timing normal function call...");
begin=GetTickCount();
ThreadFunc(0);
elapsed=GetTickCount()-begin;
printf("function call took: %d.%.03d seconds\n\n",
elapsed/1000,elapsed%1000);


puts("Time thread+ busy loop...");
begin=GetTickCount();
hThrd=CreateThread(NULL,0,ThreadFunc,(LPVOID)1,0,&threadId);

for(;;)
{
GetExitCodeThread(hThrd,&exitcode);
if(exitcode!=STILL_ACTIVE)
break;
//this chews up lots of cpu times
}

elapsed=GetTickCount()-begin;
printf("Thread + busy loop took: %d.%.03d seconds\n",
elapsed/1000,elapsed%1000);
CloseHandle(hThrd);

return EXIT_SUCCESS;

}

出错提示如下：
Linking...
LIBCD.lib(wincrt0.obj) : error LNK2001: unresolved external symbol _WinMain@16
Debug/1.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

[weakwater]

The linker is looking for the entry point for a console application, but the application is being compiled and linked as a windows application (i.e. not a console application).

This error has been observed after changing the project settings from using MBCS to UNICODE characters.

Resolved:

Under the project settings, under the ‘Link’ tab, category ‘output’, set the ‘Entry-point symbol’ to ‘wWinMainCRTStartup’.

[weakwater]

choose "output" after "category "