[Interest] Why use the sleep () function

[erlin]

This is a function that allows me to make a streaming video using 
libvlc_vlm_add_broadcast () and libvlc_vlm_play_media () Bookseller 
libvlc part of VLC. They use the function sleep () and I want to know 
why they use it.
I searched many places, and meeting all the same, but none explains why 
I needed the sleep.
I wonder if there is another alternative. I speak little English and 
have restricted Internet. Please respond is very important to me.
>> void Streaming::ejecutar(QString sout,QString target)
>> {
>>
>>       const char* params[] = {"screen-top=0",
>>                                  "screen-left=0",
>>                                  "screen-width=640",
>>                                  "screen-height=480",
>>                                  "screen-fps=30"};
>>          libvlc_instance_t *inst = libvlc_new(0, NULL);
>>          libvlc_vlm_add_broadcast(inst, "mybroad",
>>                  target.toAscii(),
>>                  sout.toAscii(),
>>                  5, params, // <= 5 == sizeof(params) == count of parameters
>>                  1, 0);
>>          libvlc_vlm_play_media(inst, "mybroad");
>>          sleep(10); //Here is the doubt
>>          libvlc_vlm_stop_media(inst,"mybroad");
>>          libvlc_vlm_release(inst);
>>
>> }