18c2ecf20Sopenharmony_ci.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 28c2ecf20Sopenharmony_ci.. c:namespace:: DTV.fe 38c2ecf20Sopenharmony_ci 48c2ecf20Sopenharmony_ci.. _FE_READ_STATUS: 58c2ecf20Sopenharmony_ci 68c2ecf20Sopenharmony_ci******************** 78c2ecf20Sopenharmony_ciioctl FE_READ_STATUS 88c2ecf20Sopenharmony_ci******************** 98c2ecf20Sopenharmony_ci 108c2ecf20Sopenharmony_ciName 118c2ecf20Sopenharmony_ci==== 128c2ecf20Sopenharmony_ci 138c2ecf20Sopenharmony_ciFE_READ_STATUS - Returns status information about the front-end. This call only requires - read-only access to the device 148c2ecf20Sopenharmony_ci 158c2ecf20Sopenharmony_ciSynopsis 168c2ecf20Sopenharmony_ci======== 178c2ecf20Sopenharmony_ci 188c2ecf20Sopenharmony_ci.. c:macro:: FE_READ_STATUS 198c2ecf20Sopenharmony_ci 208c2ecf20Sopenharmony_ci``int ioctl(int fd, FE_READ_STATUS, unsigned int *status)`` 218c2ecf20Sopenharmony_ci 228c2ecf20Sopenharmony_ciArguments 238c2ecf20Sopenharmony_ci========= 248c2ecf20Sopenharmony_ci 258c2ecf20Sopenharmony_ci``fd`` 268c2ecf20Sopenharmony_ci File descriptor returned by :c:func:`open()`. 278c2ecf20Sopenharmony_ci 288c2ecf20Sopenharmony_ci``status`` 298c2ecf20Sopenharmony_ci pointer to a bitmask integer filled with the values defined by enum 308c2ecf20Sopenharmony_ci :c:type:`fe_status`. 318c2ecf20Sopenharmony_ci 328c2ecf20Sopenharmony_ciDescription 338c2ecf20Sopenharmony_ci=========== 348c2ecf20Sopenharmony_ci 358c2ecf20Sopenharmony_ciAll Digital TV frontend devices support the ``FE_READ_STATUS`` ioctl. It is 368c2ecf20Sopenharmony_ciused to check about the locking status of the frontend after being 378c2ecf20Sopenharmony_cituned. The ioctl takes a pointer to an integer where the status will be 388c2ecf20Sopenharmony_ciwritten. 398c2ecf20Sopenharmony_ci 408c2ecf20Sopenharmony_ci.. note:: 418c2ecf20Sopenharmony_ci 428c2ecf20Sopenharmony_ci The size of status is actually sizeof(enum fe_status), with 438c2ecf20Sopenharmony_ci varies according with the architecture. This needs to be fixed in the 448c2ecf20Sopenharmony_ci future. 458c2ecf20Sopenharmony_ci 468c2ecf20Sopenharmony_ciint fe_status 478c2ecf20Sopenharmony_ci============= 488c2ecf20Sopenharmony_ci 498c2ecf20Sopenharmony_ciThe fe_status parameter is used to indicate the current state and/or 508c2ecf20Sopenharmony_cistate changes of the frontend hardware. It is produced using the enum 518c2ecf20Sopenharmony_ci:c:type:`fe_status` values on a bitmask 528c2ecf20Sopenharmony_ci 538c2ecf20Sopenharmony_ciReturn Value 548c2ecf20Sopenharmony_ci============ 558c2ecf20Sopenharmony_ci 568c2ecf20Sopenharmony_ciOn success 0 is returned. 578c2ecf20Sopenharmony_ci 588c2ecf20Sopenharmony_ciOn error -1 is returned, and the ``errno`` variable is set 598c2ecf20Sopenharmony_ciappropriately. 608c2ecf20Sopenharmony_ci 618c2ecf20Sopenharmony_ciGeneric error codes are described at the 628c2ecf20Sopenharmony_ci:ref:`Generic Error Codes <gen-errors>` chapter. 63