C# CLR 中学习 C++关键词extern使用详解_C 语言

extern size_t gc_global_mechanisms[MAX_GLOBAL_GC_MECHANISMS_COUNT];
extern DWORD g_dwHandles;
// The single GC heap instance, shared with the VM.
extern IGCHeapInternal* g_theGCHeap;
extern PTR_VOID GetUnwindDataBlob(TADDR moduleBase, PTR_RUNTIME_FUNCTION pRuntimeFunction, /* out */ SIZE_T * pSize);
extern "C" uint32_t* g_gc_card_table;
extern "C" uint8_t* g_gc_lowest_address;
extern "C"
{
    uint8_t *g_gc_sw_ww_table = nullptr;
    bool g_gc_sw_ww_enabled_for_gc_heap = false;
}

#include <iostream>
#include <Windows.h>
int k = 10;
const char* ch = "abcde";
int main()
{
	printf("ch=%d", strlen(ch));
}

#include <stdio.h>
void fly() {
	printf("hello world");
}
int main()
{
}

// page.cpp
#include <stdio.h>
extern "C"
{
	void fly() {
		printf("hello");
	}
}
void fly2() {
	printf("hello");
}

// ConsoleApplication.cpp
#include <iostream>
extern "C" void fly();
extern void fly2();
int main()
{
	fly();
	fly2();
	return 0;
}