strings

[a.mlw.walker]

Hi,

So i am trying to improve programs i write. My programs are usually for calculations due to my uni course.

At the moment my programs take in integers using scanf, but if someone puts a letter in by mistake, they crash so i want to use strings.

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

int main()
{
    char *a, *b, *c;
    printf("Please input a, b and c in the form of a b c\n");
    scanf("%s", a);
    scanf("%s", b);
    scanf("%s", c);
    printf ("%s %s %s", a, b, c);
    return 0;
}

If i completely remove anything to do with b and c, the program can print a, but once b and c come along, it crashes. What am i doing wrong? I have no idea of the length these variables could be so i cant use arrays i dont think.

is there a neater way of doing this?
thanks

[vart]

your a,b,c are uninitialized pointers - you do not know where they point - so you are trying to write to the random memory location.


You need arrays - to own the memory you'll use

char buf[100];
scanf("%99s", buf);
printf("%s", buf);

[a.mlw.walker]

thank you. what does the 99 do?

[matsp]

thank you. what does the 99 do?

Make sure that you don't read in more data than there is space for.

--
Mats