修改：添加了我的其余代码，以便更容易看到
我在尝试访问头文件中某些结构的值时收到了分段错误。
这是courses.c：
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include "structs.h"
void createStudents () {
int random, i;
for (i = 0; i < 12; i++) {
students[i].firstName = firstName[i];
students[i].lastName = lastName[i];
random = 10000 + rand() % 89999;
students[i].num.studentNum = random;
printf("%d - %s, %s \n", students[i].num.studentNum, students[i].lastName, students[i].firstName);
}
}
void createCourses () {
int numbers[999];
int numbersLeft = 999;
char courseCode[512];
char courseCode1[512];
char courseCode2[512];
int numCourses = 3;
int random, i, j;
for (i = 0; i < 999; i++) {
numbers[i] = i;
}
for (j = 0; j < 1; j++) {
random = rand() % numbersLeft;
if (random < 10) {
snprintf(courseCode, sizeof courseCode, "CS00%d", random);
courses[0].cCode = courseCode;
}
else if (random < 100 && random > 9) {
snprintf(courseCode, sizeof courseCode, "CS0%d", random);
courses[0].cCode = courseCode;
}
else if (random > 99){
snprintf(courseCode, sizeof courseCode, "CS%d", random);
courses[0].cCode = courseCode;
}
courses[0].cName = courseName[0];
courses[0].cDescription = courseDescription[0];
numbers[random] = numbers[numbersLeft-1];
numbersLeft--;
random = 4 + rand() % 4;
courses[0].maxRegister = random;
}
for (j = 0; j < 1; j++) {
random = rand() % numbersLeft;
if (random < 10) {
snprintf(courseCode1, sizeof courseCode1, "CS00%d", random);
courses[1].cCode = courseCode1;
}
else if (random < 100 && random > 9) {
snprintf(courseCode1, sizeof courseCode1, "CS0%d", random);
courses[1].cCode = courseCode1;
}
else if (random > 99){
snprintf(courseCode1, sizeof courseCode1, "CS%d", random);
courses[1].cCode = courseCode1;
}
courses[1].cName = courseName[1];
courses[1].cDescription = courseDescription[1];
numbers[random] = numbers[numbersLeft-1];
numbersLeft--;
random = 4 + rand() % 4;
courses[1].maxRegister = random;
}
for (j = 0; j < 1; j++) {
random = rand() % numbersLeft;
if (random < 10) {
snprintf(courseCode2, sizeof courseCode2, "CS00%d", random);
courses[2].cCode = courseCode2;
}
else if (random < 100 && random > 9) {
snprintf(courseCode2, sizeof courseCode2, "CS0%d", random);
courses[2].cCode = courseCode2;
}
else if (random > 99){
snprintf(courseCode2, sizeof courseCode2, "CS%d", random);
courses[2].cCode = courseCode2;
}
courses[2].cName = courseName[2];
courses[2].cDescription = courseDescription[2];
numbers[random] = numbers[numbersLeft-1];
numbersLeft--;
random = 4 + rand() % 4;
courses[2].maxRegister = random;
}
}
void regiserStudents () {
int checkSum = 0, checkSum1 = 0, checkTemp = 0, count0 = 0, count1 = 0, count2 = 0;
int wCount0 = 0, wCount1 = 0, wCount2 = 0;
int v, i, j, random, max0, max1, max2;
max0 = courses[0].maxRegister;
max1 = courses[1].maxRegister;
max2 = courses[2].maxRegister;
for (i = 0; i < 2; i++) {
checkTemp = count0;
for (j = 0; j < 12; j++) {
random = rand() % 3;
if (random == 0) {
if (count0 == 0) {
courses[random].registered[count0] = &students[j];
count0++;
}
else {
checkSum1 = students[j].num.studentNum;
for (v = 0; v < checkTemp; v++) {
checkSum = courses[0].registered[v]->num.studentNum;
if (checkSum == checkSum1) {
/*Do Nothing*/
}
else if (count0 == max0) {
courses[random].waitlisted[count0] = &students[j];
wCount0++;
}
else {
courses[random].registered[count0] = &students[j];
count0++;
}
/*}*/
}
}
}
if (random == 1) {
if (count1 == 0) {
courses[random].registered[count1] = &students[j];
count1++;
}
else {
checkSum1 = students[j].num.studentNum;
for (v = 0; v < checkTemp; v++) {
checkSum = courses[1].registered[v]->num.studentNum;
if (checkSum == checkSum1) {
/*Do Nothing*/
}
else if (count1 == max1) {
courses[random].waitlisted[count1] = &students[j];
wCount1++;
}
else {
courses[random].registered[count1] = &students[j];
count1++;
}
}
}
}
if (random == 2) {
if (count2 == 0) {
courses[random].registered[count2] = &students[j];
count2++;
}
else {
checkSum1 = students[j].num.studentNum;
for (v = 0; v < checkTemp; v++) {
checkSum = courses[2].registered[v]->num.studentNum;
if (checkSum == checkSum1) {
/*Do Nothing*/
}
else if (count2 == max2) {
courses[random].waitlisted[count2] = &students[j];
wCount2++;
}
else {
courses[random].registered[count2] = &students[j];
count2++;
}
}
}
}
}
}
courses[0].studentRegistered = count0;
courses[1].studentRegistered = count1;
courses[2].studentRegistered = count2;
courses[0].studentWaitlisted = wCount0;
courses[1].studentWaitlisted = wCount1;
courses[2].studentWaitlisted = wCount2;
}
void printCourses () {
int i;
printf("\n%s - %s: %s\nRegistered Students (%d/%d):\n", courses[0].cCode, courses[0].cName, courses[0].cDescription, courses[0].studentRegistered, courses[0].maxRegister);
for (i = 0; i < courses[0].studentRegistered; i++) {
printf("* %d - %s, %s \n", courses[0].registered[i]->num.studentNum, courses[0].registered[i]->lastName, courses[0].registered[i]->firstName);
}
printf("Waitlisted Students (%d)", courses[0].studentWaitlisted);
if (courses[0].studentWaitlisted == 0) {
printf("\n");
}
else {
for (i = 0; i < courses[0].studentWaitlisted; i++) {
printf("* %d - %s, %s \n", courses[0].waitlisted[i]->num.studentNum, courses[0].waitlisted[i]->lastName, courses[0].waitlisted[i]->firstName);
}
}
printf("\n%s - %s: %s\nRegistered Students (%d/%d):\n", courses[1].cCode, courses[1].cName, courses[1].cDescription, courses[1].studentRegistered, courses[1].maxRegister);
for (i = 0; i < courses[1].studentRegistered; i++) {
printf("* %d - %s, %s \n", courses[1].registered[i]->num.studentNum, courses[1].registered[i]->lastName, courses[1].registered[i]->firstName);
}
printf("\n%s - %s: %s\nRegistered Students (%d/%d):\n", courses[2].cCode, courses[2].cName, courses[2].cDescription, courses[2].studentRegistered, courses[2].maxRegister);
for (i = 0; i < courses[2].studentRegistered; i++) {
printf("* %d - %s, %s \n", courses[2].registered[i]->num.studentNum, courses[2].registered[i]->lastName, courses[2].registered[i]->firstName);
}
}
这是我的头文件
structs.h
#ifndef STRUCTS_H_
#define STRUCTS_H_
char *firstName[] = {
"Emma", "Liam", "Olivia",
"Noah", "Ava", "Logan",
"Sophia", "Lucas", "Isabella",
"Mason", "Shaylyn", "Jack"
};
char *lastName[] = {
"Smith", "Johnson", "Williams",
"Brown", "Jones", "Miller",
"Davis", "Garcia", "Rodriguez",
"Wilson", "Seguin", "Loveday"
};
typedef struct{
int studentNum;
}studentNumber;
typedef struct{
char *firstName;
char *lastName;
studentNumber num;
}studentID;
studentID students[12];
char *courseName[] = {"Web Programming", "Technical Communication", "Processor Architecture"};
char *courseDescription[] = {"Learn the language of HTML, and how to create websites.", "Learn the essentials of communication skills, and how to apply them on the job.", "Learn the basics of circuits and Machine Language coding."};
typedef struct {
int maxRegister;
char *cCode;
char *cName;
char *cDescription;
studentID *registered[8];
studentID *waitlisted[12];
int studentRegistered;
int studentWaitlisted;
}course;
course courses[3];
#endif
打印注册学生的价值可以正常工作，但是当我打印候补名单的学生时，我会收到分段错误。我使用gdb并发现它在这条线上，但无法找出原因：
printf("%d - %s, %s \n", courses[0].waitlisted[i]->num.studentNum, courses[0].waitlisted[i]->lastName, courses[0].waitlisted[i]->firstName);
答案 0 :(得分：0)
studentID *waitlisted[12];这意味着他们将保存结构studentID的变量的地址。您根本没有这样做，但开始访问这些指针变量。您已将它们传递给scanf，因为尝试读取未初始化的指针变量而调用未定义的行为。
那么你需要做什么 -
courses[i].waitlisted = malloc(sizeof *courses[i].waitlisted * courses[i].studentWaitlisted);
同样适用于studentID。此处fistName是char*，您需要分配一些内容才能访问它，否则它就是UB。
或
typedef struct{
char firstName[100]; //you are considering that name length would be 100
//at max.
char lastName[100];
studentNumber num;
}studentID;
你得到的seg错误是因为在它的生命周期结束后访问了一个局部变量。
courses[0].cCode = courseCode;
你能做的是
courses[0].cCode = strdup(courseCode);
初始化数组int numbers[999]={0};否则您可能会访问垃圾值，因为索引是随机数geneartion的结果。
if( random < 999){
numbers[random] = numbers[numbersLeft-1];
numbersLeft--;
}
else{
fprintf(stderr, "%s\n","Error" );
}
很多重复的代码。你应该删除重复的代码。而且也不需要single-iteration-for-loop。