c - reading a date with sscanf

Question

I've got to read a date format (dd-mm-yyyy;) from a char* string using sscanf with this line of code:

sscanf(string, "%[^-]-%[^-]-%[^;];", day, month, year)

where day/month/year are char* string of 3/3/5 elemets each.

In this way it works but when i try to use day/moth/year as integer variables (with same sscanf), I got a 0 0 0 value when i use printf on them. If i change sscanf to

sscanf(string, "%d-%d-%d;", day, month, year)

I got segmentation fault.

Anyone can help me? Using K&R book, I didn't find a solution.

Answer 1

You need to pass the address of the int variables:

int day, month, year;
sscanf(string, "%d-%d-%d;", &day, &month, &year);

sscanf() returns the number of assignments made, recommend checking the return value before using day, month and year:

if (3 == sscanf(string, "%d-%d-%d;", &day, &month, &year))
{
}