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copied!<p>The following code addresses multiple problems - not only does it make sure that strings are "safely" copied (using <code>strncpy</code>, and terminating the string with a <code>'\0'</code>), but it also makes sure you don't create a second copy of all the data in memory (not a problem with a toy example, but why start with bad habits).</p> <pre><code>#include <stdio.h> #include <string.h> #include <stdlib.h> struct students //Defining structure for students { int id; //Students ID Number char name[30]; //Students Name int age; //Students Age char dept[4]; //Studets Department int grade; //Students Grade }; int main() { struct students list[20]; FILE *f; char line[30]; char **temp = NULL; int num_righ = 0; int id5; int age5; int grade5; int i, k=0; char *newLine; f = fopen("records.txt", "r"); int s = 0; // this is the "state" counter - it goes from 0 to 4, then back to 0 while(fgets(line, sizeof (line), f) != NULL) { newLine = strchr(line, '\n'); if(newLine) *newLine='\0'; // terminate string on the newline. switch(s) { case 0: list[k].id = atoi(line); break; case 1: strncpy(list[k].name, line, 30); list[k].name[29]='\0'; // make sure it is terminated break; case 2: list[k].age = atoi(line); break; case 3: strncpy(list[k].dept, line, 3); list[k].dept[3] = '\0'; // make sure it is terminated break; case 4: list[k].grade = atoi(line); break; } s++; if (s == 5) { s = 0; k++; // if it's 5, go back to zero and start reading next structure } } fclose(f); for (i = 0; i < k; i++) { printf("id: %d\n", list[i].id); printf("name: %s", list[i].name); printf("age: %d\n", list[i].age); printf("dept: %s\n", list[i].dept); printf("grade: %d\n\n", list[i].grade); } } </code></pre>

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