Declaration

size_t strftime(char* cpOutput,
                size_t qMaxSize,
                const char* kcpFormat,
                const tm* kqpTimePtr);

Description

This function takes in a time specification through the pointer "kqpTimePtr" and a format request through the argument "kcpFormat" and outputs a text time description in the char array buffer that is passed in as "cpOutput." The argument "qMaxSize" is the maximum number of characters used in the description and the value returned is the actual length of the text description outputted in "cpOutput."

Format Table

Token	Substitution	Range	Example
%a	Weekday (Abbreviated Name)	Sun, Mon, Tue, Wed, Thu, Fri, Sat	Mon
%A	Weekday (Full Name)	Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday	Sunday
%b	Month (Abbreviated Name)	Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec	Jan
%B	Month (Full Name)	January, February, March, April, May, June, July, August, September, October, November, December	February
%c	Date/Time Representation (Locale)	Any Date and Time	10/10/18 08:19:38
%d	Day of Month	[01, 31]	03
%H	Hour in 24 hour format	[00, 23]	14
%I	Hour in 12 hour format	[00, 11]	09
%j	Day of the year	[001, 366]	034
%m	Month (as number)	[01, 12]	04
%M	Minute	[00, 59]	00
%p	Ante Meridiem or Post Meridiem	AM, PM	AM
%S	Second	[00, 59]	45
%U	Week (as number) – Sunday Start	[00, 53]	07
%w	Weekday (as number, 0 = Sunday)	[0, 6]	5
%W	Week (as number) – Monday Start	[00, 53]	43
%x	Local Date Representation	Any Date	10/10/18
%X	Local Time Representation	Any Time	08:19:38
%y	Year Modulo 100	[00, 99]	24
%Y	Year	Any Year	2008
%z	Time Zone (Locale)	Any Time Zone	Central Standard Time
%Z	Time Zone (Locale)	Any Time Zone	Central Standard Time
%%	Percent Sign	—	—
%#c	Long Date/Time Representation (Locale)	Any Date and Time	Saturday, October 18, 2008 08:32:11
%#x	Long Date Representation (Locale)	Any Date	Saturday, October 18, 2008
%#d, %#H, %#I, %#j, %#m, %#M, %#S, %#U, %#w, %#W, %#y, %#Y	Removes Leading Zeros	—	—
%#a, %#A, %#b, %#B, %#p, %#X, %#z, %#Z, %#%	Ignored	—	—

Example

#include <iostream>
#include <ctime>

int main() {
    using namespace std;

    time_t qTime;
    tm* qpTimeSpec;
    // Get the number of seconds since midnight Jan. 1, 1970
    time(&qTime);
    // Convert the seconds to a tm struct variable
    qpTimeSpec = gmtime(&qTime);

    char caTime[100];
    size_t qActualLength = strftime(caTime, 100, "%I:%M %p", qpTimeSpec);
    cout << "Written length = " << qActualLength << endl;
    cout << "Time = " << caTime << endl;

    return 0;
}

Output