Issue

This Content is from Stack Overflow. Question asked by jms1980

I have a date string in format YYYYMMDDHH that I am trying to split into year YYYY month MM day DD, and hour HH.

Below is my code in which I am attempting to do this:

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>

int main()
{
    char datetime[10];
    char year;
    char month;
    char day;
    char hour;

    sprintf(datetime,"2022092300");
    sscanf(datetime,"%4s%2s%2s%2s",year,month,day,hour);
    printf("year is %s month is %sn",year,month);

}

Unfortunately this code is not giving me a value for year and month and I doubt it would for day and hour. How do I tweak this code to get the desired results parsing the string into YYYYMMDDHH into YYYY, MM, DD, HH?

Solution

When reading strings, you must pass the address of a string as argument.

Also, strings must be terminated with a null (zero) character value. So if you expect a string to hold 10 characters, it must be 11 characters long to include the null terminator.

#include <stdio.h>

int main(void)
{
    char datetime[11];
    char year[5];
    char month[3];
    char day[3];
    char hour[3];

    sprintf(datetime,"2022092300");
    sscanf(datetime,"%4s%2s%2s%2s",year,month,day,hour);
    printf("year is %s month is %s\n",year,month);
}

EDIT

I meant to mention this, but forgot. You should turn your compiler warnings up to at least -Wall -Wextra -pedantic-errors if using GCC or Clang or /W3 if using MSVC. If you are using an IDE you will need to use Google to find how to adjust the compiler error/warning level for that IDE.

This Question was asked in StackOverflow by jms1980 and Answered by Dúthomhas It is licensed under the terms of CC BY-SA 2.5. - CC BY-SA 3.0. - CC BY-SA 4.0.