Morse Code

I'm trying to build morse code, but seems like I cannot find the way to operate the duration of the beep. Could someone help me with this problem?
Thank you

There's no portable way to do this. We'll have to know your OS at least.

I guess my OS is windows 7.

( You guess?! :confused: )
Your best bet would be the WinAPI Beep function

Another thread for moderators to move. This is not a C problem. It is a Windows programming problem.