Syntax:
#include <ctime> size_t strftime( char *str, size_t maxsize, const char *fmt, struct tm *time );
The function strftime() formats date and time information from time to a format specified by fmt, then stores the result in str (up to maxsize characters).
Certain codes may be used in fmt to specify different types of time:
| Code | Meaning | 
|---|---|
| %a | abbreviated weekday name (e.g. Fri) | 
| %A | full weekday name (e.g. Friday) | 
| %b | abbreviated month name (e.g. Oct) | 
| %B | full month name (e.g. October) | 
| %c | the standard date and time string | 
| %d | day of the month, as a number (1-31) | 
| %H | hour, 24 hour format (0-23) | 
| %I | hour, 12 hour format (1-12) | 
| %j | day of the year, as a number (1-366) | 
| %m | month as a number (1-12). Note: some versions of Microsoft Visual C++ may use values that range from 0-11. | 
| %M | minute as a number (0-59) | 
| %p | locale's equivalent of AM or PM | 
| %S | second as a number (0-59) | 
| %U | week of the year, (0-53), where week 1 has the first Sunday | 
| %w | weekday as a decimal (0-6), where Sunday is 0 | 
| %W | week of the year, (0-53), where week 1 has the first Monday | 
| %x | standard date string | 
| %X | standard time string | 
| %y | year in decimal, without the century (0-99) | 
| %Y | year in decimal, with the century | 
| %Z | time zone name | 
| %% | a percent sign | 
The strftime() function returns the number of characters put into str, or zero if an error occurs.