请教:头文件有什么用啊?
谢谢各位了
程序代码：
/*
* conio.h
* This file has no copyright assigned and is placed in the Public Domain.
* This file is a part of the mingw-runtime package.
* No warranty is given; refer to the file DISCLAIMER within the package.
*
* Low level console I/O functions. Pretty please try to use the ANSI
* standard ones if you are writing new code.
*
*/#ifndef _CONIO_H_
#define _CONIO_H_/* All the headers include this file. */
#include <_mingw.h>#ifndef RC_INVOKED
#ifdef __cplusplus
extern \"C\" {
#endif_CRTIMP char* __cdecl _cgets (char*);
_CRTIMP int __cdecl _cprintf (const char*, ...);
_CRTIMP int __cdecl _cputs (const char*);
_CRTIMP int __cdecl _cscanf (char*, ...);_CRTIMP int __cdecl _getch (void);
_CRTIMP int __cdecl _getche (void);
_CRTIMP int __cdecl _kbhit (void);
_CRTIMP int __cdecl _putch (int);
_CRTIMP int __cdecl _ungetch (int);
#ifndef _NO_OLDNAMES_CRTIMP int __cdecl getch (void);
_CRTIMP int __cdecl getche (void);
_CRTIMP int __cdecl kbhit (void);
_CRTIMP int __cdecl putch (int);
_CRTIMP int __cdecl ungetch (int);#endif /* Not _NO_OLDNAMES */
#ifdef __cplusplus
}
#endif#endif /* Not RC_INVOKED */
#endif /* Not _CONIO_H_ */
