'睡眠'的冲突类型

当我尝试运行程序时,为什么一直收到错误消息"'睡眠'的冲突类型"？

#include 
#include 

void congratulateStudent (char *student, char *course, int numDays)
{
    printf("%s has done as much %s Programming as I could fit into %d days. \n", student, course, numDays);
}

int main(int argc, const char * argv[])
{
    congratulateStudent("Mark", "Cocoa", 5);
    sleep(2);
    congratulateStudent("Bo", "Objective-C", 2);
    sleep(2);
    congratulateStudent("Mike", "Python", 5);
    sleep(2);
    congratulateStudent("Ted", "iOS", 5);

    return 0;
}

user3386109.. 6

每个库函数都有一个相应的头文件来声明该函数.对于该sleep函数,该头文件是unistd.h.每个函数的文档都会告诉您要使用哪个头文件.

如果您没有包含正确的头文件,那么编译器会抱怨.不要让编译器不开心,总是包含正确的头文件.