exit, _Exit, _exit

Terminates the calling process. The exit function terminates it after cleanup; _exit and _Exit terminate it immediately.

Бележка

Do not use this method to shut down a Universal Windows Platform (UWP) app, except in testing or debugging scenarios. Programmatic or UI ways to close a Store app are not permitted according to the Microsoft Store policies. For more information, see UWP app lifecycle. For more information about UWP apps, see Universal Windows Platform documentation.

Syntax

C

void exit(
   int const status
);
void _Exit(
   int const status
);
void _exit(
   int const status
);

Parameters

status
Exit status code.

Remarks

The exit, _Exit and _exit functions terminate the calling process. The exit function calls destructors for thread-local objects, then calls—in last-in-first-out (LIFO) order—the functions that are registered by atexit and _onexit, and then flushes all file buffers before it terminates the process. The _Exit and _exit functions terminate the process without destroying thread-local objects or processing atexit or _onexit functions, and without flushing stream buffers.

Although the exit, _Exit and _exit calls don't return a value, the value in status is made available to the host environment or waiting calling process, if one exists, after the process exits. Typically, the caller sets the status value to 0 to indicate a normal exit, or to some other value to indicate an error. The status value is available to the operating-system batch command ERRORLEVEL and is represented by one of two constants: EXIT_SUCCESS, which represents a value of 0, or EXIT_FAILURE, which represents a value of 1.

The exit, _Exit, _exit, quick_exit, _cexit, and _c_exit functions behave as follows.

Function	Description
exit	Performs complete C library termination procedures, terminates the process, and provides the supplied status code to the host environment.
_Exit	Performs minimal C library termination procedures, terminates the process, and provides the supplied status code to the host environment.
_exit	Performs minimal C library termination procedures, terminates the process, and provides the supplied status code to the host environment.
quick_exit	Performs quick C library termination procedures, terminates the process, and provides the supplied status code to the host environment.
_cexit	Performs complete C library termination procedures and returns to the caller. Doesn't terminate the process.
_c_exit	Performs minimal C library termination procedures and returns to the caller. Doesn't terminate the process.

When you call the exit, _Exit or _exit function, the destructors for any temporary or automatic objects that exist at the time of the call aren't called. An automatic object is a non-static local object defined in a function. A temporary object is an object that's created by the compiler, such as a value returned by a function call. To destroy an automatic object before you call exit, _Exit, or _exit, explicitly call the destructor for the object, as shown here:

C++

void last_fn() {}
    struct SomeClass {} myInstance{};
    // ...
    myInstance.~SomeClass(); // explicit destructor call
    exit(0);
}

Don't use DLL_PROCESS_ATTACH to call exit from DllMain. To exit the DLLMain function, return FALSE from DLL_PROCESS_ATTACH.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Requirements

Function	Required header
exit, _Exit, _exit	<process.h> or <stdlib.h>

For more compatibility information, see Compatibility.

Example

C

// crt_exit.c
// This program returns an exit code of 1. The
// error code could be tested in a batch file.

#include <stdlib.h>

int main( void )
{
   exit( 1 );
}

See also

Process and environment control
abort
atexit
_cexit, _c_exit
_exec, _wexec functions
_onexit, _onexit_m
quick_exit
_spawn, _wspawn functions
system, _wsystem