# _Exit

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< c‎ | program

Defined in header `<stdlib.h>` |  |
void _Exit( int exit_code ); |  | (since C99) (until C11)
_Noreturn void _Exit( int exit_code ); |  | (since C11) (until C23)
[[noreturn]] void _Exit( int exit_code ); |  | (since C23)

Causes normal program termination to occur without completely cleaning the resources.

Functions passed to at_quick_exit() or atexit() are not called. Whether open streams with unwritten buffered data are flushed, open streams are closed, or temporary files are removed is implementation-defined.

If `exit_code` is 0 or EXIT_SUCCESS, an implementation-defined status indicating successful termination is returned to the host environment. If `exit_code` is EXIT_FAILURE, an implementation-defined status, indicating unsuccessful termination, is returned. In other cases an implementation-defined status value is returned.

### Parameters

exit_code | - | exit status of the program

### Return value

(none)

### Example

Run this code

    #include <stdlib.h>
    #include <stdio.h>

    /* _Exit does not call functions registered with atexit. */
    void f1(void)
    {
        puts("pushed first");
    }

    void f2(void)
    {
        puts("pushed second");
    }

    int main(void)
    {
        printf("Enter main()\n");
        atexit(f1);
        atexit(f2);
        fflush(stdout);   /* _Exit may not flush unwritten buffered data */
        _Exit(0);
    }

Output:

    Enter main()

### References

- C17 standard (ISO/IEC 9899:2018):

  - 7.22.4.5 The _Exit function (p: 256)

- C11 standard (ISO/IEC 9899:2011):

  - 7.22.4.5 The _Exit function (p: 352)

- C99 standard (ISO/IEC 9899:1999):

  - 7.20.4.4 The _Exit function (p: 316)

### See also

abort | causes abnormal program termination (without cleaning up) (function)
exit | causes normal program termination with cleaning up (function)

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