Я пишу WIN32 C -программу для КПК Motorola M C -55A с использованием Windows Mobile 5.0 SDK. Я пытаюсь узнать текущую дату и время. Я пытался использовать time_t, но получаю ошибку компоновщика: «неразрешенное время внешнего символа, на которое ссылается функция BasicScanPro c». У меня нет синтаксических ошибок. Я также пытался использовать функцию ctime, struct tm, SYSTEMTIME, но все они терпят неудачу с одной и той же ошибкой компоновщика выше.
Я проверил файл заголовка и все вышеупомянутые переменные, структуры и функции ( time_t, ctime (), et c) были объявлены в этом заголовочном файле, но почему-то я не могу использовать их в коде. Вот мой код:
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <windows.h>
#include <windowsx.h>
//Variables declaration
time_t current_time;
// Forward declarations
LRESULT CALLBACK BasicScanProc(HWND,UINT,WPARAM,LPARAM);
void ErrorExit(HWMD, UINT, LPTSTR);
LPTSTR LoadMsg(UINT, LPTSTR, int);
int WINAPI WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPWSTR lpszCmdLine,
int nCmdShow)
{
int nResult;
hInst = hInstance; // save the instance handle to a global variable
nResult = DialogBox(hInstance, MAKEINTRESOURCE(IDD_DIALOG_SSCAN), NULL,
BasicScanProc);
return nResult;
}
LRESULT CALLBACK BasicScanProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
DWORD dwResult;
TCHAR szLabelType[256];
TCHAR szLen[MAX_PATH];
TCHAR szMsgBuf[256];
LPSCAN_BUFFER lpScanBuf;
HWND hctl_data, hctl_length, hctl_type, hctl1, hctl2, hWndComboBox;
switch(uMsg)
{
case WM_INITDIALOG:
//Below fails with error : 'time_t' : illegal use of this type as an expression
//C:\Program Files (x86)\Windows Mobile 5.0 SDK R2\PocketPC\include\ARMV4I\stdlib.h :
//see declaration of 'time_t'
current_time = time(NULL);
printf("Hours since January 1, 1970 = %ld\n", current_time/3600);
//This also fails
//time_t now;
//time(&now);
Содержимое time.h для Windows Mobile 5.0 SDK выглядит следующим образом: -
/***
*time.h - definitions/declarations for time routines
*
* Copyright (c) 1985-1994, Microsoft Corporation. All rights reserved.
*
*Purpose:
* This file has declarations of time routines and defines
* the structure returned by the localtime and gmtime routines and
* used by asctime.
* [ANSI/System V]
*
****/
#ifndef _INC_TIME
#define _INC_TIME
#ifdef __cplusplus
extern "C" {
#endif
/* Define _CRTAPI1 (for compatibility with the NT SDK) */
#ifndef _CRTAPI1
#if ( (_MSC_VER >= 800) && (_M_IX86 >= 300) )
#define _CRTAPI1 __cdecl
#else
#define _CRTAPI1
#endif
#endif
/* Define _CRTAPI2 (for compatibility with the NT SDK) */
#ifndef _CRTAPI2
#if ( (_MSC_VER >= 800) && (_M_IX86 >= 300) )
#define _CRTAPI2 __cdecl
#else
#define _CRTAPI2
#endif
#endif
/* Define _CRTIMP */
#ifndef _CRTIMP
#ifdef _NTSDK
/* definition compatible with NT SDK */
#define _CRTIMP
#else /* ndef _NTSDK */
/* current definition */
#ifdef _DLL
#define _CRTIMP __declspec(dllimport)
#else /* ndef _DLL */
#define _CRTIMP
#endif /* _DLL */
#endif /* _NTSDK */
#endif /* _CRTIMP */
/* Define __cdecl for non-Microsoft compilers */
#if ( !defined(_MSC_VER) && !defined(__cdecl) )
#define __cdecl
#endif
#ifndef _WCHAR_T_DEFINED
typedef unsigned short wchar_t;
#define _WCHAR_T_DEFINED
#endif
/* Define the implementation defined time type */
#ifndef _TIME_T_DEFINED
typedef long time_t; /* time value */
#define _TIME_T_DEFINED /* avoid multiple def's of time_t */
#endif
#ifndef _CLOCK_T_DEFINED
typedef long clock_t;
#define _CLOCK_T_DEFINED
#endif
#ifndef _SIZE_T_DEFINED
typedef unsigned int size_t;
#define _SIZE_T_DEFINED
#endif
/* Define NULL pointer value */
#ifndef NULL
#ifdef __cplusplus
#define NULL 0
#else
#define NULL ((void *)0)
#endif
#endif
#ifndef _TM_DEFINED
struct tm {
int tm_sec; /* seconds after the minute - [0,59] */
int tm_min; /* minutes after the hour - [0,59] */
int tm_hour; /* hours since midnight - [0,23] */
int tm_mday; /* day of the month - [1,31] */
int tm_mon; /* months since January - [0,11] */
int tm_year; /* years since 1900 */
int tm_wday; /* days since Sunday - [0,6] */
int tm_yday; /* days since January 1 - [0,365] */
int tm_isdst; /* daylight savings time flag */
};
#define _TM_DEFINED
#endif
/* Clock ticks macro - ANSI version */
#define CLOCKS_PER_SEC 1000
/* Extern declarations for the global variables used by the ctime family of
* routines.
*/
#ifdef _NTSDK
#ifdef _DLL
/* Declarations and definitions compatible with the NT SDK */
#define _daylight (*_daylight_dll)
#define _timezone (*_timezone_dll)
/* non-zero if daylight savings time is used */
extern int * _daylight_dll;
/* difference in seconds between GMT and local time */
extern long * _timezone_dll;
/* standard/daylight savings time zone names */
extern char ** _tzname;
#else /* ndef _DLL */
#ifdef _POSIX_
extern char * _rule;
#endif /* _POSIX_ */
/* non-zero if daylight savings time is used */
extern int _daylight;
/* difference in seconds between GMT and local time */
extern long _timezone;
/* standard/daylight savings time zone names */
#ifdef _POSIX_
extern char * tzname[2];
#else /* ndef _POSIX_ */
extern char * _tzname[2];
#endif /* _POSIX_ */
#endif /* _DLL */
#else /* ndef _NTSDK */
/* Current declarations and definitions */
#if defined(_DLL) && defined(_M_IX86)
#define _daylight (*__p__daylight())
_CRTIMP int * __cdecl __p__daylight(void);
#define _timezone (*__p__timezone())
_CRTIMP long * __cdecl __p__timezone(void);
#define _tzname (__p__tzname())
_CRTIMP char ** __cdecl __p__tzname(void);
#else /* !(defined(_DLL) && defined(_M_IX86)) */
/* non-zero if daylight savings time is used */
_CRTIMP extern int _daylight;
/* difference in seconds between GMT and local time */
_CRTIMP extern long _timezone;
/* standard/daylight savings time zone names */
_CRTIMP extern char * _tzname[2];
#endif /* defined(_DLL) && defined(_M_IX86) */
#endif /* _NTSDK */
/* Function prototypes */
_CRTIMP char * __cdecl asctime(const struct tm *);
_CRTIMP char * __cdecl ctime(const time_t *);
_CRTIMP clock_t __cdecl clock(void);
/*
_CRTIMP double __cdecl difftime(time_t, time_t);
*/
_CRTIMP struct tm * __cdecl gmtime(const time_t *);
_CRTIMP struct tm * __cdecl localtime(const time_t *);
_CRTIMP time_t __cdecl mktime(struct tm *);
_CRTIMP size_t __cdecl strftime(char *, size_t, const char *,
const struct tm *);
_CRTIMP char * __cdecl _strdate(char *);
_CRTIMP char * __cdecl _strtime(char *);
_CRTIMP time_t __cdecl time(time_t *);
#ifdef _POSIX_
_CRTIMP void __cdecl tzset(void);
#else
_CRTIMP void __cdecl _tzset(void);
#endif
/* --------- The following functions are OBSOLETE --------- */
/* The Win32 API GetLocalTime and SetLocalTime should be used instead. */
unsigned __cdecl _getsystime(struct tm *);
unsigned __cdecl _setsystime(struct tm *, unsigned);
/* --------- The preceding functions are OBSOLETE --------- */
#ifndef _SIZE_T_DEFINED
typedef unsigned int size_t;
#define _SIZE_T_DEFINED
#endif
#ifndef _WTIME_DEFINED
/* wide function prototypes, also declared in wchar.h */
_CRTIMP wchar_t * __cdecl _wasctime(const struct tm *);
_CRTIMP wchar_t * __cdecl _wctime(const time_t *);
_CRTIMP size_t __cdecl wcsftime(wchar_t *, size_t, const char *,
const struct tm *);
_CRTIMP wchar_t * __cdecl _wstrdate(wchar_t *);
_CRTIMP wchar_t * __cdecl _wstrtime(wchar_t *);
#define _WTIME_DEFINED
#endif
#if !__STDC__ || defined(_POSIX_)
/* Non-ANSI names for compatibility */
#define CLK_TCK CLOCKS_PER_SEC
#ifdef _NTSDK
/* Declarations and definitions compatible with the NT SDK */
#define daylight _daylight
/* timezone cannot be #defined to _timezone because of <sys/timeb.h> */
#ifndef _POSIX_
#define tzname _tzname
#define tzset _tzset
#endif /* _POSIX_ */
#else /* ndef _NTSDK */
/* Current declarations */
_CRTIMP extern int daylight;
_CRTIMP extern long timezone;
_CRTIMP extern char * tzname[2];
_CRTIMP void __cdecl tzset(void);
#endif /* _NTSDK */
#endif /* __STDC__ */
#ifdef __cplusplus
}
#endif
#endif /* _INC_TIME */
Как мне успешно получить текущую дату и время в моей C -программе? Заранее спасибо.