SDL_Init

Use this function to initialize the SDL library. This must be called before using any other SDL function.
使用这个函数可以初始化SDL库，在使用SDL其他的库函数之前必须被调用。

Syntax 语法

int SDL_Init(Uint32 flags)

Function Parameters 函数相关参数

Return Value 返回值

Returns 0 on success or a negative error code on failure; call SDL_GetError() for more information.
返回0成功，负数则失败，可以通过调用函数 SDL_GetError 获取错误详情。

Code Examples 代码示例

C

#include "SDL.h"
#include <stdio.h> /* for fprintf() */
#include <stdlib.h> /* for atexit() */
int main(int argc, char** argv) {
    if (SDL_Init(SDL_INIT_VIDEO|SDL_INIT_TIMER) != 0) {
        fprintf(stderr,
                "\nUnable to initialize SDL:  %s\n",
                SDL_GetError()
               );
        return 1;
    }
    atexit(SDL_Quit);
    /* ... */
    return 0;
}

C++

切换行号显示
#include <exception>
#include <string>
#include "SDL.h"
class InitError: public std::exception {
    public:
        InitError();
        InitError(const std::string&);
        virtual ~InitError() throw();
        virtual const char* what() const throw();
    private:
        std::string msg;
};
InitError::InitError():
  exception(), msg(SDL_GetError()) {}
InitError::InitError(const std::string& m):
  exception(), msg(m) {}
InitError::~InitError() throw() {}
const char* InitError::what() const throw() {
    return msg.c_str();
}
class SDL {
    public:
        SDL(Uint32 flags = 0) throw(InitError);
        virtual ~SDL();
};
SDL::SDL(Uint32 flags) throw(InitError) {
    if (SDL_Init(flags) != 0)
        throw InitError();
}
SDL::~SDL() {
    SDL_Quit();
}
/* ... */
#include <iostream>
int main(int argc, char **argv) {
    try {
        SDL sdl(SDL_INIT_VIDEO|SDL_INIT_TIMER);
        /* ... */
        return 0;
    }
    catch (const InitError& err) {
        std::cerr
            << "Error while initializing SDL:  "
            << err.what() << std::endl;
    }
    return 1;
}

Remarks 注意

SDL_Init() simply forwards to calling SDL_InitSubSystem().

Therefore, the two may be used interchangeably.

Though for readability of your code SDL_InitSubSystem() might be preferred.

The File I/O and Threading subsystems are initialized by default.

You must specifically initialize other subsystems if you use them in your application.

flags may be any of the following OR’d together:

If you want to initialize subsystems separately you would call SDL_Init(0) followed by SDL_InitSubSystem() with the desired subsystem flag.

Related Functions 相关函数

1. SDL_InitSubSystem
2. SDL_Quit
3. SDL_SetMainReady
4. SDL_WasInit