Scanf() string pointer problem

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# 8  
Old 11-14-2013
Please show your complete code.
# 9  
Old 11-14-2013
Here it is:
#include <stdio.h>
#include <stdlib.h>

struct Student {
    int studentNumber;
    int phoneNumber;
    char *studentName;        //Line 7
//    char studentName[20]; //Line 8

int main()
    struct Student *list;
    int numOfStudents;
    int x;
    int studentCounter = 1;
    printf("\nEnter the number of students you would like to input: ");
    scanf("%d", &numOfStudents);
    list = malloc(sizeof(list) * numOfStudents);
    for (x = 0; x < numOfStudents; x++) {
    printf("\nEnter name for student #%d: ", studentCounter);
    scanf("%s", list[x].studentName);        //Line 25
    printf("Enter student number for student #%d: ",
    scanf("%d", &list[x].studentNumber);            //Line27
    printf("Enter phone number for student #%d: ",
    scanf("%d", &list[x].phoneNumber);            //Line 29

    for (x = 0; x < numOfStudents; x++) {
    printf("%s, #%d, %d: \n", list[x].studentName, list[x].studentNumber, list[x].phoneNumber);
//        free(list[x].studentName);                 //Line 35
for (x = 0; x < numOfStudents; x++) { free(list[x].studentName); }  //Line 37
    free(list);                        //Line 38
    return 0;

Thanks again!
# 10  
Old 11-14-2013
This was subtle. It took me a while to spot it.


What is list? A pointer.

Remember from your other thread, what you get when you do sizeof(pointer) ? It takes you completely literally and gives you the size of the pointer. Which means you only allocate 4 or 8 bytes for the size of each index, and end up going way beyond the end when you loop.

sizeof(struct Student)

This User Gave Thanks to Corona688 For This Post:
# 11  
Old 11-14-2013
That was really subtle and, fundamental, too. I can't get it until you pointed out!
This bugged me sooooo much, and I had thought my understanding is totally wrong. Fortunately I am on the right track, not that far away from right, at least.
Thank you very much again!
This User Gave Thanks to yifangt For This Post:
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