The following example function sends the play command with the "from" and "to" flags.
DWORD PlayFromTo(LPSTR lpstrAlias, DWORD dwFrom, DWORD dwTo)
{
char achCommandBuff[128];
wsprintf(achCommandBuff, "play %s from %u to %u",
lpstrAlias, dwFrom, dwTo);
return mciSendString(achCommandBuff, NULL, 0, NULL);
}