[root@fedora ~]# cat flush.c
#include <stdio.h>

int main() {
        char test[1];
        fprintf(stderr,"hello\n");
        fflush(stderr);
        sprintf(test,"aaaaaaaaaaa");
        return 0;
};
[root@fedora ~]# gcc flush.c -o flush
[root@fedora ~]# ./flush
hello
Erreur de segmentation
[root@fedora ~]#