18c2ecf20Sopenharmony_ci.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 28c2ecf20Sopenharmony_ci.. c:namespace:: DTV.fe 38c2ecf20Sopenharmony_ci 48c2ecf20Sopenharmony_ci.. _FE_GET_INFO: 58c2ecf20Sopenharmony_ci 68c2ecf20Sopenharmony_ci***************** 78c2ecf20Sopenharmony_ciioctl FE_GET_INFO 88c2ecf20Sopenharmony_ci***************** 98c2ecf20Sopenharmony_ci 108c2ecf20Sopenharmony_ciName 118c2ecf20Sopenharmony_ci==== 128c2ecf20Sopenharmony_ci 138c2ecf20Sopenharmony_ciFE_GET_INFO - Query Digital TV frontend capabilities and returns information 148c2ecf20Sopenharmony_ciabout the - front-end. This call only requires read-only access to the device. 158c2ecf20Sopenharmony_ci 168c2ecf20Sopenharmony_ciSynopsis 178c2ecf20Sopenharmony_ci======== 188c2ecf20Sopenharmony_ci 198c2ecf20Sopenharmony_ci.. c:macro:: FE_GET_INFO 208c2ecf20Sopenharmony_ci 218c2ecf20Sopenharmony_ci``int ioctl(int fd, FE_GET_INFO, struct dvb_frontend_info *argp)`` 228c2ecf20Sopenharmony_ci 238c2ecf20Sopenharmony_ciArguments 248c2ecf20Sopenharmony_ci========= 258c2ecf20Sopenharmony_ci 268c2ecf20Sopenharmony_ci``fd`` 278c2ecf20Sopenharmony_ci File descriptor returned by :c:func:`open()`. 288c2ecf20Sopenharmony_ci 298c2ecf20Sopenharmony_ci``argp`` 308c2ecf20Sopenharmony_ci pointer to struct :c:type:`dvb_frontend_info` 318c2ecf20Sopenharmony_ci 328c2ecf20Sopenharmony_ciDescription 338c2ecf20Sopenharmony_ci=========== 348c2ecf20Sopenharmony_ci 358c2ecf20Sopenharmony_ciAll Digital TV frontend devices support the :ref:`FE_GET_INFO` ioctl. It is 368c2ecf20Sopenharmony_ciused to identify kernel devices compatible with this specification and to 378c2ecf20Sopenharmony_ciobtain information about driver and hardware capabilities. The ioctl 388c2ecf20Sopenharmony_citakes a pointer to dvb_frontend_info which is filled by the driver. 398c2ecf20Sopenharmony_ciWhen the driver is not compatible with this specification the ioctl 408c2ecf20Sopenharmony_cireturns an error. 418c2ecf20Sopenharmony_ci 428c2ecf20Sopenharmony_cifrontend capabilities 438c2ecf20Sopenharmony_ci===================== 448c2ecf20Sopenharmony_ci 458c2ecf20Sopenharmony_ciCapabilities describe what a frontend can do. Some capabilities are 468c2ecf20Sopenharmony_cisupported only on some specific frontend types. 478c2ecf20Sopenharmony_ci 488c2ecf20Sopenharmony_ciThe frontend capabilities are described at :c:type:`fe_caps`. 498c2ecf20Sopenharmony_ci 508c2ecf20Sopenharmony_ciReturn Value 518c2ecf20Sopenharmony_ci============ 528c2ecf20Sopenharmony_ci 538c2ecf20Sopenharmony_ciOn success 0 is returned. 548c2ecf20Sopenharmony_ci 558c2ecf20Sopenharmony_ciOn error -1 is returned, and the ``errno`` variable is set 568c2ecf20Sopenharmony_ciappropriately. 578c2ecf20Sopenharmony_ci 588c2ecf20Sopenharmony_ciGeneric error codes are described at the 598c2ecf20Sopenharmony_ci:ref:`Generic Error Codes <gen-errors>` chapter. 60