[SOLVED] printing with fgets function

ad_alta · 08-04-2012, 05:29 PM

Can someone tell me what is wrong here. I want to loop the array and print each student data on a single line, but instead I get each member data on a separate line.

Enter first name for student 1: James
Enter last name for student 1: Wilson
Enter age of student: 25
Enter first name for student 2: Jamie
Enter last name for student 2: Wilson
Enter age of student: 22
You entered:
James
Wilson
25
Jamie
Wilson
22

Code:

#include <stdio.h>

int main()
{
 struct person {
        char firstName[11];
        char lastName[16];
        int age;
 };

 int count=2,i,ch;


 

 struct person student[count];

 for( i=0; i < count; i++)
   {
     printf("Enter first name for student %d: ", i + 1);
     fgets(student[i].firstName,10,stdin);
     printf("Enter last name for student %d: ", i +1);
     fgets(student[i].lastName,15,stdin);
     printf("Enter age of student: ");
     fscanf(stdin," %d", &student[i].age);
     ch=getchar();
   }

 printf("You entered: \n");

 for( i=0; i < count; i++)
 {
     printf("%s %s %d\n", student[i].firstName, student[i].lastName,student[i].age);
}
return 0;

}

NevemTeve · 08-05-2012, 12:15 AM

After fgets you might want to remove the tailing LineFeed (and perhaps check for problems)

Code:

    buff= '\0';
    fgets (buff, max, stdin);
    len= strlen (buff);
    if (len==0) /* error/EOF on input? */
    else if (buff[len-1]=='\n')
        buff [len--]= '\0';
    else if (len==max-1) /* line truncated */

ad_alta · 08-06-2012, 02:36 AM

Thank you for the response NevemTeve. Why do you check for the '\n' char at buff[len-1] when strlen returns the number of characters in the string? I'm only assuming here, but shouldn't it be buff[len+1] for '\0' and buff[len+2] for '\n'.

segmentation_fault · 08-08-2012, 04:17 AM

You shouldn't mix using fgets and fscanf/scanf, because they handle whitespace characters differently, so some newline characters (\n) are get with fgets.

As for strlen, yes, it returns the length of the string without \0. So, on a string (lets name it buf) containing "James" and a newline character you have:

Code:

 J a m e s \n \0
 0 1 2 3 4  5  6

strlen(buf) will return 6, but you want to get rid of buf[5] which is buf[strlen(buf) - 1]