Opening a file
#include <iostream>
#include <string>
using namespace std;
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
main(int argc, char **argv)
{
int fd = open(argv[1], O_RDONLY);
if(fd < 0)
cerr << "File open failed." << endl;
else {
char buf[1024];
int nchr;
while((nchr = read(fd, buf, sizeof buf)) > 0)
cout.write(buf, nchr);
}
}