Syntax

  #include <time.h>  
   
  time_t mktime  (  
     struct tm   *timeptr);
  

Parameters

timeptr

(IN) Points to the structure containing the time information to convert.

Return Values

Returns the converted calendar time. On error, -1 will be returned cast as type (time_t). To test for an error condition, compare the return value to (time_t) -1.

Remarks

mktime converts the time information in the structure pointed to by the timeptr parameter into a calendar time with the same encoding used by the time function.

See Also

asctime, asctime_r, clock, ctime, ctime_r, difftime, gmtime, gmtime_r, localtime, localtime_r, strftime, time

Example

  #include <stdio.h>  
  #include <time.h> 
   
  static const char *week_day[ ] =  
  {  
     "Sunday", "Monday", "Tuesday", "Wednesday",  
     "Thursday", "Friday", "Saturday"  
  };  
   
  main ()  
  {  
     struct tm new_year;  
     new_year.tm_year = 2001 - 1900;  
     new_year.tm_mon  = 0;  
     new_year.tm_mday = 1;  
     new_year.tm_hour = 0;  
     new_year.tm_min  = 0;  
     new_year.tm_sec  = 0;  
     new_year.tm_isdst = 0;  
     mktime (&new_year);  
     printf ("The next century begins on a %s\n",  
        week_day [new_year.tm_wday] );  
  }
  

produces the following:

  The next century begins on a Monday