将结构写入文本文件

因此，我最近掌握了结构，终于对数组感到满意，现在我必须处理我的教授希望我能够存储100万个结构（工资记录）的文件，而且我敢肯定，大数组会导致程序崩溃。因此，我对如何将结构备份到txt文件并在启动时将其上传回我的程序感到困惑。文字会乱七八糟吗？这是我程序的主要部分，我需要将其放入文件中。它基本上使用struct制作工资记录。所以我只是想知道有人能给我提示将其发送到文本文件中吗

void payRollAdd(PAYROLL employee[], long int *pCounter){    
    int userinput;
    do{
        printf("Enter Employee Name:\n");
        fgets(employee[*pCounter].name, 40, stdin);
        printf("Please Enter the paydate(mmddyyyy):\n");
        scanf_s("%02d%02d%d", &employee[*pCounter].payDate.month, &employee[*pCounter].payDate.day, &employee[*pCounter].payDate.year);
        printf("Enter Employee Age:\n");
        scanf_s("%d", &employee[*pCounter].age);
        printf("Enter Employee Hours Worked\n");
        scanf_s("%f", &employee[*pCounter].hrsWorked);
        printf("Enter Employee Hourly Wage:\n");
        scanf_s("%f", &employee[*pCounter].hrlyWage);
        printf("  Employee Data \n");
        printf("Name: %s\n", employee[*pCounter].name);
        printf("Age:  %d\n", employee[*pCounter].age);
        printf("Pay Date: %02d/%02d/%d:\n", employee[*pCounter].payDate.month, employee[*pCounter].payDate.day, employee[*pCounter].payDate.year);
        printf("Hours Worked: %0.2f\n", employee[*pCounter].hrsWorked);
        printf("Hourly Wage: $%0.2f\n", employee[*pCounter].hrlyWage);


        if (employee[*pCounter].hrsWorked > 40.00){
            float temp = 40.00;
            employee[*pCounter].regPay = temp * employee[*pCounter].hrlyWage;
            printf("Regular pay: $%0.2f\n", employee[*pCounter].regPay);
        }
        else
        {
            employee[*pCounter].regPay = employee[*pCounter].hrsWorked * employee[*pCounter].hrlyWage;
            printf("Regular pay: $%0.2f\n", employee[*pCounter].regPay);
        }
        if (employee[*pCounter].hrsWorked > 40.00){
            float temp2 = 0.00;
            temp2 = employee[*pCounter].hrsWorked;
            temp2 -= 40.00;
            employee[*pCounter].otPay = temp2 * `(employee[*pCounter].hrlyWage + (employee[*pCounter].hrlyWage / 2.00));`
            printf("OT pay: $%0.2f\n", employee[*pCounter].otPay);
        }
        else
        {
            employee[*pCounter].otPay = 0;
            printf("OT pay: $0\n");
        }
        employee[*pCounter].totalPay = employee[*pCounter].regPay + employee[*pCounter].otPay;
        printf("Total Pay: $%0.2f\n", employee[*pCounter].totalPay);