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.. SPDX-License-Identifier: GPL-2.0
.. _GPIO_GET_LINEINFO_IOCTL:
***********************
GPIO_GET_LINEINFO_IOCTL
***********************
.. warning::
This ioctl is part of chardev_v1.rst and is obsoleted by
gpio-v2-get-lineinfo-ioctl.rst.
Name
====
GPIO_GET_LINEINFO_IOCTL - Get the publicly available information for a line.
Synopsis
========
.. c:macro:: GPIO_GET_LINEINFO_IOCTL
``int ioctl(int chip_fd, GPIO_GET_LINEINFO_IOCTL, struct gpioline_info *info)``
Arguments
=========
``chip_fd``
The file descriptor of the GPIO character device returned by `open()`.
``info``
The :c:type:`line_info<gpioline_info>` to be populated, with the
``offset`` field set to indicate the line to be collected.
Description
===========
Get the publicly available information for a line.
This information is available independent of whether the line is in use.
.. note::
The line info does not include the line value.
The line must be requested using gpio-get-linehandle-ioctl.rst or
gpio-get-lineevent-ioctl.rst to access its value.
Return Value
============
On success 0 and ``info`` is populated with the chip info.
On error -1 and the ``errno`` variable is set appropriately.
Common error codes are described in error-codes.rst.
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