EXIT_SUCCESS, EXIT_FAILURE

#define EXIT_SUCCESS /*implementation defined*/

#define EXIT_FAILURE /*implementation defined*/

The EXIT_SUCCESS and EXIT_FAILURE macros expand into integral expressions that can be used as arguments to the exit function (and, therefore, as the values to return from the main function), and indicate program execution status.

Notes

Both EXIT_SUCCESS and the value zero indicate successful program execution status (see exit), although it is not required that EXIT_SUCCESS equals zero.

Example

#include <stdio.h>
#include <stdlib.h>
 
int main(void)
{
    FILE *fp = fopen("data.txt","r");
    if (fp == NULL)
    {
       fprintf(stderr, "fopen() failed in file %s at line # %d", __FILE__,__LINE__);
       exit(EXIT_FAILURE);
    }
 
    /* Normal processing continues here. */
    fclose(fp);
    printf("Normal Return\n");
 
    return EXIT_SUCCESS;
}

fopen() failed in file main.cpp at line # 9

References

• C17 standard (ISO/IEC 9899:2018):
• 7.22/3 General utilities <stdlib.h> (p: 248)
• C11 standard (ISO/IEC 9899:2011):
• 7.22/3 General utilities <stdlib.h> (p: 340)
• C99 standard (ISO/IEC 9899:1999):
• 7.20/3 General utilities <stdlib.h> (p: 306)
• C89/C90 standard (ISO/IEC 9899:1990):
• 4.10 General utilities <stdlib.h>

See also