exit

 

C

Language

Headers

Type support

Program utilities

Variadic function support

Error handling

Dynamic memory management

Strings library

Algorithms

Numerics

Date and time utilities

Input/output support

Localization support

Concurrency support (C11)

Technical Specifications

Symbol index

 

Program support utilities

Program termination
abort exit quick_exit (C11) _Exit (C99)	atexit at_quick_exit (C11) EXIT_SUCCESSEXIT_FAILURE
Unreachable control flow
unreachable (C23)
Communicating with the environment
system	getenvgetenv_s (C11)
Signals
signal raise sig_atomic_t	SIG_DFLSIG_IGN SIG_ERR
Signal types
SIGABRTSIGFPESIGILLSIGINTSIGSEGVSIGTERM
Non-local jumps
setjmp
longjmp
Types
jmp_buf

 

Defined in header <stdlib.h>
void exit( int exit_code );		(until C11)
_Noreturn void exit( int exit_code );		(since C11)

Causes normal program termination to occur.

Several cleanup steps are performed:

• functions passed to atexit are called, in reverse order of registration
• all C streams are flushed and closed
• files created by tmpfile are removed
• control is returned to the host environment. If exit_code is zero or EXIT_SUCCESS, an implementation-defined status, indicating successful termination is returned. If exit_code is EXIT_FAILURE, an implementation-defined status, indicating unsuccessful termination is returned. In other cases implementation-defined status value is returned.

Notes

The functions registered with at_quick_exit are not called.

The behavior is undefined if a program calls exit more than once, or if it calls exit and quick_exit

The behavior is undefined if during a call to a function registered with atexit, the function exits with longjmp.

Returning from the the main function, either by a return statement or by reaching the end of the function, executes exit(), passing the argument of the return statement (or ​0​ if implicit return was used) as exit_code.

Parameters

exit_code

-

exit status of the program

Return value

(none)

Example

Run this code

#include <stdio.h>
#include <stdlib.h>
 
int main(void)
{
    FILE *fp = fopen("data.txt","r");
    if (fp == NULL) {
       fprintf(stderr, "error opening file data.txt in function main()\n");
       exit( EXIT_FAILURE );
    }
    fclose(fp);
    printf("Normal Return\n");
    return EXIT_SUCCESS ;
}

Possible output:

error opening file data.txt in function main()

References

• C17 standard (ISO/IEC 9899:2018):

• 7.22.4.4 The exit function (p: 256)

• C11 standard (ISO/IEC 9899:2011):

• 7.22.4.4 The exit function (p: 351-352)

• C99 standard (ISO/IEC 9899:1999):

• 7.20.4.3 The exit function (p: 315-316)

• C89/C90 standard (ISO/IEC 9899:1990):

• 4.10.4.3 The exit function

See also

abort	causes abnormal program termination (without cleaning up) (function)
atexit	registers a function to be called on exit() invocation (function)
quick_exit (C11)	causes normal program termination without completely cleaning up (function)