C语言笔记——时间运算

http://www.cnblogs.com/VRS_technology/archive/2010/09/21/1832564.html

prehourTime ()

{

time_t curtime;

time_t resulttime;

struct tm *st;

time (&curtime);

st = localtime (&curtime);

st->tm_hour -= 1;

resulttime = mktime (st);

st = localtime (&resulttime);

return st;

}

struct tm *prehourTime ();

struct tm *prehour = prehourTime ();

char fn[100];

char fn2[100];

char fp[100]; //file path

char year[5];

char month[2];

char day[2];

char hour[2];

sprintf (year, "%d", prehour->tm_year + 1900);

sprintf (month, "%02d", prehour->tm_mon + 1);

sprintf (day, "%02d", prehour->tm_mday);

sprintf (hour, "%02d", prehour->tm_hour);