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diff --git a/Documentation/media/uapi/dvb/frontend_f_open.rst b/Documentation/media/uapi/dvb/frontend_f_open.rst deleted file mode 100644 index 6a46ec5acf7b..000000000000 --- a/Documentation/media/uapi/dvb/frontend_f_open.rst +++ /dev/null @@ -1,117 +0,0 @@ -.. Permission is granted to copy, distribute and/or modify this -.. document under the terms of the GNU Free Documentation License, -.. Version 1.1 or any later version published by the Free Software -.. Foundation, with no Invariant Sections, no Front-Cover Texts -.. and no Back-Cover Texts. A copy of the license is included at -.. Documentation/media/uapi/fdl-appendix.rst. -.. -.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections - -.. _frontend_f_open: - -*************************** -Digital TV frontend open() -*************************** - -Name -==== - -fe-open - Open a frontend device - - -Synopsis -======== - -.. code-block:: c - - #include <fcntl.h> - - -.. c:function:: int open( const char *device_name, int flags ) - :name: dvb-fe-open - -Arguments -========= - -``device_name`` - Device to be opened. - -``flags`` - Open flags. Access can either be ``O_RDWR`` or ``O_RDONLY``. - - Multiple opens are allowed with ``O_RDONLY``. In this mode, only - query and read ioctls are allowed. - - Only one open is allowed in ``O_RDWR``. In this mode, all ioctls are - allowed. - - When the ``O_NONBLOCK`` flag is given, the system calls may return - ``EAGAIN`` error code when no data is available or when the device - driver is temporarily busy. - - Other flags have no effect. - - -Description -=========== - -This system call opens a named frontend device -(``/dev/dvb/adapter?/frontend?``) for subsequent use. Usually the first -thing to do after a successful open is to find out the frontend type -with :ref:`FE_GET_INFO`. - -The device can be opened in read-only mode, which only allows monitoring -of device status and statistics, or read/write mode, which allows any -kind of use (e.g. performing tuning operations.) - -In a system with multiple front-ends, it is usually the case that -multiple devices cannot be open in read/write mode simultaneously. As -long as a front-end device is opened in read/write mode, other open() -calls in read/write mode will either fail or block, depending on whether -non-blocking or blocking mode was specified. A front-end device opened -in blocking mode can later be put into non-blocking mode (and vice -versa) using the F_SETFL command of the fcntl system call. This is a -standard system call, documented in the Linux manual page for fcntl. -When an open() call has succeeded, the device will be ready for use in -the specified mode. This implies that the corresponding hardware is -powered up, and that other front-ends may have been powered down to make -that possible. - - -Return Value -============ - -On success :ref:`open() <frontend_f_open>` returns the new file descriptor. -On error, -1 is returned, and the ``errno`` variable is set appropriately. - -Possible error codes are: - - -On success 0 is returned, and :c:type:`ca_slot_info` is filled. - -On error -1 is returned, and the ``errno`` variable is set -appropriately. - -.. tabularcolumns:: |p{2.5cm}|p{15.0cm}| - -.. flat-table:: - :header-rows: 0 - :stub-columns: 0 - :widths: 1 16 - - - - ``EPERM`` - - The caller has no permission to access the device. - - - - ``EBUSY`` - - The the device driver is already in use. - - - - ``EMFILE`` - - The process already has the maximum number of files open. - - - - ``ENFILE`` - - The limit on the total number of files open on the system has been - reached. - - -The generic error codes are described at the -:ref:`Generic Error Codes <gen-errors>` chapter. |