exit c+

exit() is a library function in C/C++ programming language, it is used to terminate the calling process (function) immediately i.e. we can say it is used for the normal program termination and also perform the several cleanup steps.

exit()是C / C ++編程語言中的一個庫函數，它用于立即終止調用進程(函數)，即可以說它用于正常程序終止并執行幾個清理步驟。

Syntax:

句法：

void exit(int status);

Parameter(s): status – defines the exit status.

參數： status –定義退出狀態。

There are two status that we can define,

我們可以定義兩種狀態，

Return value: The return type of the function is void, it returns nothing.

返回值：函數的返回類型為void ，不返回任何內容。

1) exit(0) or exit(EXIT_SUCCESS)

1)退出(0)或退出(EXIT_SUCCESS)

exit(0) is used to terminate the program by specifying the successful execution of the program.

exit(0)用于通過指定程序的成功執行來終止程序。

Syntax:

句法：

exit(0);

2) exit(1) or exit(EXIT_FAILURE)

2)退出(1)或退出(EXIT_FAILURE)

exit(1) is used to terminate the program by specifying the successful execution of the program.

exit(1)用于通過指定程序的成功執行來終止程序。

Syntax:

句法：

exit(1);

Example 1:

范例1：

Here, we are reading two numbers and then dividing them, if the second number is 0 then exiting the program using exit(1) and if the second number is not 0 then performing the division operation and exiting the program using exit(0).

在這里，我們正在讀取兩個數字，然后將它們相除，如果第二個數字為0，則使用exit(1)退出程序；如果第二個數字不為0，則執行除法運算，然后使用exit(0)退出程序。

// C++ program to demonstrate the
// example of exit(0) and exit(1)
#include <iostream>
using namespace std;
int main()
{
int a;
int b;
cout << "Enter divisor  (value of a): ";
cin >> a;
cout << "Enter dividend (value of b): ";
cin >> b;
cout << "a: " << a << endl;
cout << "b: " << b << endl;
if (b == 0) {
cout << "Dividend must not be 0..." << endl;
// EXIT_FAILURE
exit(1);
}
cout << a << "/" << b << " : " << (float)a / (float)b << endl;
// EXIT_SUCCESS
exit(0);
}

Output:

輸出：

RUN 1:
Enter divisor  (value of a): 10
Enter dividend (value of b): 3
a: 10
b: 3
10/3 : 3.33333
RUN 2:
Enter divisor  (value of a): 10
Enter dividend (value of b): 0
a: 10
b: 0
Dividend must not be 0...

Example 2:

范例2：

Here, we are opening a file in read-only mode, if the file doe not exit then exiting the program using exit(1), and file exists then closing it and exiting the program using exit(0).

在這里，我們以只讀模式打開文件，如果文件沒有退出，則使用exit(1)退出程序，并且文件存在，然后將其關閉并使用exit(0)退出程序。

// C++ program to demonstrate the
// example of exit(0) and exit(1)
#include <stdio.h>
#include <stdlib.h>
int main()
{
FILE* fPtr;
// opening the file
fPtr = fopen("hello1.txt", "r");
// checking whether file exists or not
if (fPtr == NULL) {
printf("oops, file does not exist...");
// EXIT_FAILURE
exit(1);
}
printf("File opened successfully...");
// clsoing the file
fclose(fPtr);
// EXIT_SUCCESS
exit(0);
}

Output:

輸出：

oops, file does not exist...

出口(0)和出口(1)之間的區別 (Difference between exit(0) and exit(1))

exit(0);

exit(0);

翻譯自: https://www.includehelp.com/cpp-tutorial/exit-0-vs-exit-1-in-c-cpp-with-examples.aspx

exit c+