c++ - beep not working (linux) -


i'm trying beep, can't. i've tried:

#include <iostream> using namespace std; int main(int argc, char **argv) {     cout << '\a' << flush;     return 0; }

i have tried using this: http://www.johnath.com/beep/ doesn't beep.

(if run $ speaker-test -t sine -f 500 -l 2 2>&1 on terminal, beeps, beep c++ study low-level sound programming)

and able control frequency , duration.

unless you're logged in console, cout not refer system console. need open /dev/console , send \a there.

#include <stdio.h> #include <unistd.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h>  int main() {     int s = open ("/dev/console", o_wronly);     if (s < 0)         perror ("unable open console");     else     {         if (write (s, "\a", 1) != 1)             perror ("unable beep");     } }

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