将秒转换为日期的C程序。 我有以下C程序代码。
#include <sys/types.h>
#include <sys/stat.h>
#include <stdio.h>
#ifdef HAVE_ST_BIRTHTIME
# define birthtime(x) (x).st_birthtime
#else
# define birthtime(x) (x).st_ctime
#endif
int main(int argc, char *argv[])
{
struct stat st;
size_t i;
for( i=1; i<argc; i++ )
{
if( stat(argv[i], &st) != 0 )
perror(argv[i]);
printf("%i\n", birthtime(st));
}
return 0;
}
它返回从1970年1月1日到文件创建日期的秒数。如何仅使用C语言将创建的秒数转换为创建日期?
答案 0 :(得分:3)
标准C功能可以将自纪元以来的秒数转换为细分时间,具体为localtime()
或gmtime()
,具体取决于您的需求。然后,您可以使用asctime()
将细分时间转换为字符串。不要忘记#include <time.h>
并阅读相应的手册页。
答案 1 :(得分:1)
以下是我使用的一些功能:
typedef int64_t timestamp_t;
timestamp_t currentTimestamp( void )
{
struct timeval tv;
struct timezone tz;
timestamp_t timestamp = 0;
struct tm when;
timestamp_t localeOffset = 0;
{ // add localtime to UTC
localtime_r ( (time_t*)×tamp, &when);
localeOffset = when.tm_gmtoff * 1000;
}
gettimeofday (&tv, &tz );
timestamp = ((timestamp_t)((tv.tv_sec) * 1000) ) + ( (timestamp_t)((tv.tv_usec) / 1000) );
timestamp+=localeOffset;
return timestamp;
}
/* ----------------------------------------------------------------------------- */
int32_t timestampToStructtm ( timestamp_t timestamp, struct tm* dateStruct)
{
timestamp /= 1000; // required timestamp in seconds!
//localtime_r ( ×tamp, dateStruct);
gmtime_r ( ×tamp, dateStruct);
return 0;
}
/* ----------------------------------------------------------------------------- */
int32_t sprintf_timestampAsYYYYMMDDHHMMSS ( char* buf, timestamp_t timestamp )
{
int year = 0;
int month = 0;
int day = 0;
int hour = 0;
int minute = 0;
int second = 0;
struct tm timeStruct;
if (timestamp==TIMESTAMP_NULL) {
return sprintf(buf, "NULL_TIMESTAMP");
}
memset (&timeStruct, 0, sizeof (struct tm));
timestampToStructtm(timestamp, &timeStruct);
year = timeStruct.tm_year + 1900;
month = timeStruct.tm_mon + 1;
day = timeStruct.tm_mday;
hour = timeStruct.tm_hour;
minute = timeStruct.tm_min;
second = timeStruct.tm_sec;
return sprintf(buf, "%04d%02d%02d%02d%02d%02d", year, month, day, hour, minute, second);
}