求sys/time.h文件，注意不是time.h，谢谢好人帮助！
我最近在弄box2d，运行时发现缺少<sys/time.h>文件，用time.h编译就会出错，缺少gettimeofday() etc...在VS中没找到，网上也搜索了好久，希望能有好心人帮助给个链接，谢谢了！好人一生平安！ Visual?Studio c++ linux sys/time time.h
[解决办法]
VS下本来就没，提取给你
http://vdisk.weibo.com/s/wPulE

[解决办法]

#ifndef _SYS_TIME_H_
#define _SYS_TIME_H_
#include <time.h>

#ifdef__cplusplus
extern "C" {
#endif

#ifndef _TIMEVAL_DEFINED /* also in winsock[2].h */
#define _TIMEVAL_DEFINED
struct timeval {
  long tv_sec;
  long tv_usec;
};
#define timerisset(tvp) ((tvp)->tv_sec 
[解决办法]
 (tvp)->tv_usec)
#define timercmp(tvp, uvp, cmp) \
(((tvp)->tv_sec != (uvp)->tv_sec) ? \
((tvp)->tv_sec cmp (uvp)->tv_sec) : \
((tvp)->tv_usec cmp (uvp)->tv_usec))
#define timerclear(tvp) (tvp)->tv_sec = (tvp)->tv_usec = 0
#endif /* _TIMEVAL_DEFINED */

/* Provided for compatibility with code that assumes that
   the presence of gettimeofday function implies a definition
   of struct timezone. */
struct timezone
{
  int tz_minuteswest; /* of Greenwich */
  int tz_dsttime;     /* type of dst correction to apply */
};

/*
   Implementation as per:
   The Open Group Base Specifications, Issue 6
   IEEE Std 1003.1, 2004 Edition

   The timezone pointer arg is ignored.  Errors are ignored.
*/ 
int __cdecl __MINGW_NOTHROW gettimeofday(struct timeval *__restrict__,
 void *__restrict__  /*tzp (unused) */);

#ifdef__cplusplus
}
#endif


#endif /* _SYS_TIME_H_ */