Thread: string problem !!!!!!

Originally Posted by Adak

I refreshed it once, and did not see several posts in this thread. After refreshing twice more, I see them all, and that it's solved.

Adak I was not referring to you, not even want to "shout" at you

@Sharlin glad you found your way

// I wish a good day to everybody

//@Sharlin, mind that it is better to keep what you want to say in one post, and not post 2-3 times in a row

Originally Posted by jimblumberg

But remember that scanf() is just as unsafe as gets(), unless you use the width modifier. And that scanf() will not easily accept strings with spaces, for this you need something like fgets().

Code:

   char _str[100];
   int i=0,count_str=0;
   printf("enter string up to 10 letters!");
   scanf("%100s",_str);

Jim

Very good point. Thank you Jim.

For a more complete approach to line-based to address the above concerns (safe input, and embedded spaces), consider the following extended strategy and adjust for your use case:

1. read an entire input line
2. if the line is too long, abort with an error
3. parse the line
4. if the line does not contain the expected data, abort with an error
5. print the result

Here is an example (breaking into functions would help in a real program):

Code:

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

#define MAX 10000
static char inputline[MAX] = "";

int main(void)
{
    // (optional) show prompt
    printf("%s", "Enter your name using the format: LAST, FIRST.\n"
            "LAST and FIRST are allowed to have embedded spaces in them.\n"
            ": ");
    
    // get inputline and handle errors
    fgets(inputline, MAX, stdin);
    size_t len = strlen(inputline);
    if (len == 0) {
        printf("No line received.\n");
        return EXIT_FAILURE;
    }else if(len == MAX-1){
        printf("Line is too long.\n");
        return EXIT_FAILURE;
    }
    
    // parse the inputline into LAST, FIRST
    char last[100]="", first[100]="", leftover[10000]="";
    if (sscanf(inputline, " %99[^,], %99[^.].%9999c", last, first, leftover) != 3) {
        printf("Name was in the wrong format.\n");
        return EXIT_FAILURE;
    }
    len = strlen(leftover);
    if (len > 1) {
        leftover[len-1] = '\0'; // chomp the \n from leftover
        printf("Warning: trailing characters found after inputline: \"%s\"\n", leftover);
    }
    
    // show result
    printf("\nLast name: \"%s\"\n", last);
    printf("First name: \"%s\"\n", first);
    return EXIT_SUCCESS;
}

Explanations:
scanf returns the number of items it found, so in this case 3 should be expected for correct input. If the input was correct, leftover should contain "\n" (only the newline).

%99[^,], means to get at most 99 non-commas followed by a comma. Change the size and delimiter to what you need. Example: if you use ; and the buffer for that component is 1000 characters, use %999[^;];