c - 在 linux 帐户中运行 C 但在 mac 终端上运行 C 时出现错误消息

Question

我想知道我的代码在哪里以及为什么出错，导致弹出如下所示的错误消息？因为在我的终端上编译C代码工作正常，但是在linux中却不同，所以我想知道哪里出了问题。当我输入“-1”退出购买功能时，会发生错误。非常感谢您抽出时间并指出我的错误!

int purchase(void){
        char menu_code[6]; //user input meal code   
        FILE *fptr; //flie pointer for receipt text file        
        FILE *tfptr; //flie pointer for trans text file 
        FILE *mfptr; //flie pointer for combo text file
        FILE *afptr; //flie pointer for addon text file
        int quantity=0, itemFound=0,total_quantity=0;   
        float total=0, grand_total=0;
        unsigned int combo_trans=0, ala_trans=0, i;
        struct Meal meal;

        printf("Please enter a menu code (-1 to exit purchase). Example: C0001.\n");
        scanf("%s", menu_code);

        fptr = fopen("receipt.txt", "w"); //clear file before appending for each purchase       
        while(strcmp(menu_code, "-1") != 0)//while loop to compare the input with sentinel value
        {
            mfptr = fopen("combo.txt", "r");//command to open a specific file
            while(!feof(mfptr))
            {
                fscanf(mfptr, "%5[^:]:%[^:]:%f:%[^\n]\n", meal.mcode, meal.name, &meal.price, meal.description);    
                if(strcmp(menu_code, meal.mcode) == 0)
                {
                    printf("Enter the quantity of the meal: ");
                    scanf("%d",&quantity);          
                    quantity = (quantity <= 0) ? 0 : quantity; //accepting valid values for quantity                          
                    total = meal.price * quantity;
                    grand_total += total;    
                    total_quantity += quantity;                         
                    itemFound ++;
                    combo_trans++;                      
                    print_order(quantity, meal.name, meal.price, grand_total); 

                    tfptr = fopen("trans.txt", "a+");
                    fprintf(tfptr, "%u:%u:%.2f\n", quantity, 0, total); 
                    fclose(tfptr);
                    fptr = fopen("receipt.txt", "a+");
                    fprintf(fptr, "%-15u%-34s%-17.2f\n", quantity, meal.name, meal.price*quantity);
                    fclose(fptr);

                }
            }fclose(mfptr);//closes the file after execution

            if(itemFound == 0)//start of if statement
            {
                afptr = fopen("addon.txt", "r");
                while(!feof(afptr))
                {
                    fscanf(afptr, "%5[^:]:%[^:]:%f:%[^\n]\n", meal.mcode, meal.name, &meal.price, meal.description);  
                    if(strcmp(menu_code, meal.mcode) == 0)
                    {
                       printf("Enter the quantity of the meal: ");
                       scanf("%d",&quantity);          
                       quantity = (quantity <= 0) ? 0 : quantity;                             
                       total = meal.price * quantity;
                       grand_total += total;
                       total_quantity += quantity;                                 
                       itemFound ++;
                       ala_trans++;                     
                       print_order(quantity, meal.name, meal.price, grand_total); 

                       tfptr = fopen("trans.txt", "a+");
                       fprintf(tfptr, "%u:%u:%.2f\n", 0, quantity, total); 
                       fclose(tfptr);
                       fptr = fopen("receipt.txt", "a+");
                       fprintf(fptr, "%-15u%-34s%-17.2f\n", quantity, meal.name, meal.price*quantity);
                       fclose(fptr);
                    }
                }fclose(afptr);
            }//end of if statement
            if(itemFound == 0){
                printf("Invalid menu code!\n");
            }
            itemFound = 0;
            printf("Please enter a menu code (-1 to exit purchase). Example: C0001.\n");
            scanf("%s", menu_code);
        };//end of while loop
        fclose(fptr);
        print_receipt(ala_trans, combo_trans, total_quantity, grand_total);
        order();
        return 0;
    }

错误:

*** glibc detected *** ./a.out: double free or corruption (out): 0x09c392d8 ***
======= Backtrace: =========
/lib/libc.so.6(+0x70b81)[0xb75fbb81]
/lib/libc.so.6(+0x732d8)[0xb75fe2d8]
/lib/libc.so.6(fclose+0x14a)[0xb75eb6fa]
./a.out[0x804a4d6]
./a.out[0x804a693]
./a.out[0x804879f]
/lib/libc.so.6(__libc_start_main+0xe6)[0xb75a1d36]
./a.out[0x8048701]
======= Memory map: ========
08048000-0804c000 r-xp 00000000 fd:02 12853280                           /home/0333120/Assignment/a.out
0804c000-0804d000 rw-p 00003000 fd:02 12853280                           /home/0333120/Assignment/a.out
09c39000-09c5a000 rw-p 00000000 00:00 0                                  [heap]
b7567000-b7584000 r-xp 00000000 fd:02 12314805                           /lib/libgcc_s-4.4.7-20120601.so.1
b7584000-b7585000 rw-p 0001d000 fd:02 12314805                           /lib/libgcc_s-4.4.7-20120601.so.1
b758a000-b758b000 rw-p 00000000 00:00 0
b758b000-b771b000 r-xp 00000000 fd:02 12314671                           /lib/libc-2.12.so
b771b000-b771c000 ---p 00190000 fd:02 12314671                           /lib/libc-2.12.so
b771c000-b771e000 r--p 00190000 fd:02 12314671                           /lib/libc-2.12.so
b771e000-b771f000 rw-p 00192000 fd:02 12314671                           /lib/libc-2.12.so
b771f000-b7722000 rw-p 00000000 00:00 0
b7724000-b7728000 rw-p 00000000 00:00 0
b7728000-b7746000 r-xp 00000000 fd:02 12314649                           /lib/ld-2.12.so
b7746000-b7747000 r--p 0001d000 fd:02 12314649                           /lib/ld-2.12.so
b7747000-b7748000 rw-p 0001e000 fd:02 12314649                           /lib/ld-2.12.so
b7748000-b7749000 r-xp 00000000 00:00 0                                  [vdso]
bfec9000-bfede000 rw-p 00000000 00:00 0                                  [stack]
Aborted

Answer 1

我认为这个错误是由运行时问题引起的(经过一些研究，请记住，我几周前才开始学习 C，而且我对它还是新手)。打开了 2 个文件(收据和交易)，但其中任何一个都没有逻辑上关闭。因此导致程序在我的购买功能之间崩溃并失败。因此，请检查正确放置文件开头和结尾的位置。

打开要写入的文件(receipt.txt)并最终关闭它是没有意义的。因此，我将其更改为写入后立即关闭，以便每次调用函数时都以空白状态覆盖文件。