Two digit date in strftime and struct tm - c

Question

I'm doing the following to get time in "Day Month Day Year" format.
struct tm *example= localtime(&t);
strftime(buf,sizeof(buf),"%a %b %d %Y",example);
strncpy(time_buffer,buffer,sizeof(time_buffer)) ;
But if date is single digit,such as 9 it is displayed as 9. I'd like to print it as 09. Any idea how that can be done?

Answer 1

The manpage for strftime says:
%d The day of the month as a decimal number (range 01 to 31).
Which seems like what you want.
// compile with: gcc -o ex1 -Wall ex1.c
#include "stdio.h"
#include "sys/time.h"
#include "time.h"
int main (const int argc, const char ** argv ) {
time_t curr_time;
char buff[1024];
// time(&curr_time);
curr_time = 1359684105; // Thu Jan 31 2013
struct tm *now = localtime(&curr_time);
strftime(buff, sizeof(buff), "%a %b %d %Y", now);
printf("time: %ld\n", curr_time);
printf("time: %s\n", buff);
curr_time += 24 * 60 * 60; // Fri Feb 01 2013
now = localtime(&curr_time);
strftime(buff, sizeof(buff), "%a %b %d %Y", now);
printf("time: %ld\n", curr_time);
printf("time: %s\n", buff);
return 0;
}
That produces:
time: 1359684105
time: Thu Jan 31 2013
time: 1359770505
time: Fri Feb 01 2013
Which looks like what you're after. If you want to drop the leading zero, you can use %e:
%e Like %d, the day of the month as a decimal number, but a leading zero is replaced by a space. (SU)
Author reported that %d doesn't adhere to the manpage on solaris, here's an alternate solution that uses sprintf directly:
// compile with: gcc -o ex1 -Wall ex1.c
#include "stdio.h"
#include "sys/time.h"
#include "time.h"
int main (const int argc, const char ** argv ) {
time_t curr_time;
char buff[1024], daynamebuff[8], monbuff[8], daynumbuff[3], yearbuff[8];
// time(&curr_time);
curr_time = 1359684105; // Thu Jan 31 2013
curr_time += 24 * 60 * 60; // Fri Feb 01 2013
struct tm *now = localtime(&curr_time);
strftime(daynamebuff, sizeof(daynamebuff), "%a", now);
strftime(monbuff, sizeof(monbuff), "%b", now);
strftime(daynumbuff, sizeof(daynumbuff), "%e", now);
strftime(yearbuff, sizeof(yearbuff), "%Y", now);
sprintf(buff, "%s %s %02d %s", daynamebuff, monbuff, now->tm_mday, yearbuff);
printf("%s\n", buff);
return 0;
}