EXIT_SUCCESS, EXIT_FAILURE - termination status constants

EXIT_SUCCESS  and  EXIT_FAILURE represent a successful and unsuccessful exit status respectively, and can
       be used as arguments to the exit(3) function.

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

       int
       main(int argc, char *argv[])
       {
           FILE *fp;

           if (argc != 2) {
               fprintf(stderr, "Usage: %s <file>\n", argv[0]);
               exit(EXIT_FAILURE);
           }

           fp = fopen(argv[1], "r");
           if (fp == NULL) {
               perror(argv[1]);
               exit(EXIT_FAILURE);
           }

           /* Other code omitted */

           fclose(fp);
           exit(EXIT_SUCCESS);
       }

       C89, POSIX.1-2001.

       Standard C library (libc)

       EXIT_SUCCESS, EXIT_FAILURE - termination status constants

exit(3), sysexits.h(3head)

Linux man-pages 6.9.1                              2024-06-15                               EXIT_SUCCESS(3const)

       C11, POSIX.1-2008.

#include<stdlib.h>#defineEXIT_SUCCESS  0
       #defineEXIT_FAILURE  /* nonzero */