我想使用cloneOS X 上的系统调用。这是一个 Unix 系统调用，所以应该不是问题，对吧？我已经成功尝试使用fork, vfork以及其他类似的功能。这是我正在尝试的程序：
#include <sched.h> //Clone resides here
#include <stdlib.h> //standard library
#include <stdio.h>
#include <time.h>
#include <limits.h>
#include <sys/shm.h>
#include <errno.h>
#include <sys/sem.h>
#include <signal.h>
#include <sys/types.h>
int helloWorld();
int main(int argc, char *argv[])
{
int (*functionPointer)() = &helloWorld; //The first argument of clone accepts a pointer to a function which must return int
void **childStack = (void**)malloc(1024); //We will give our child 1kB of stack space
clone(functionPointer, childStack, 0, NULL); //First arugment is the function to be called, second one is our stack, CLONE_VM means to share memory, last NULL PID description
return 0;
}
int helloWorld()
{
printf("Hello (clone) world!\r\n");
return 0;
}
编译用gcc -o test my_file.c gives:
Undefined symbols for architecture x86_64:
"_clone", referenced from:
_main in ccG3qOjx.o
ld: symbol(s) not found for architecture x86_64
collect2: ld returned 1 exit status
请随意忽略评论，因为我刚刚学习。还有一件事......如果我尝试通过CLONE_VM在参数中它甚至没有编译给我错误：
my_file.c: In function ‘main’:
my_file.c:12: error: ‘CLONE_VM’ undeclared (first use in this function)
my_file.c:12: error: (Each undeclared identifier is reported only once
my_file.c:12: error: for each function it appears in.)
我是否缺少一个#include？如果有，是哪一个？
我做错了什么以及如何解决？
