.. -*- coding: utf-8; mode: rst -*- .. _FE_SET_TONE: ***************** ioctl FE_SET_TONE ***************** Name ==== FE_SET_TONE - Sets/resets the generation of the continuous 22kHz tone. Synopsis ======== .. c:function:: int ioctl( int fd, FE_SET_TONE, enum fe_sec_tone_mode *tone ) :name: FE_SET_TONE Arguments ========= ``fd`` File descriptor returned by :ref:`open() `. ``tone`` pointer to enum :c:type:`fe_sec_tone_mode` Description =========== This ioctl is used to set the generation of the continuous 22kHz tone. This call requires read/write permissions. Usually, satellite antenna subsystems require that the digital TV device to send a 22kHz tone in order to select between high/low band on some dual-band LNBf. It is also used to send signals to DiSEqC equipment, but this is done using the DiSEqC ioctls. .. attention:: If more than one device is connected to the same antenna, setting a tone may interfere on other devices, as they may lose the capability of selecting the band. So, it is recommended that applications would change to SEC_TONE_OFF when the device is not used. .. c:type:: fe_sec_tone_mode .. flat-table:: enum fe_sec_tone_mode :header-rows: 1 :stub-columns: 0 - .. row 1 - ID - Description - .. row 2 - .. _SEC-TONE-ON: ``SEC_TONE_ON`` - Sends a 22kHz tone burst to the antenna - .. row 3 - .. _SEC-TONE-OFF: ``SEC_TONE_OFF`` - Don't send a 22kHz tone to the antenna (except if the FE_DISEQC_* ioctls are called) Return Value ============ On success 0 is returned, on error -1 and the ``errno`` variable is set appropriately. The generic error codes are described at the :ref:`Generic Error Codes ` chapter.