iio_write_channel_ext_info(9)

💅 iio_write_channel_ext_info — bestie's guide to the Kernel API Manual 🎀

okay so this is a page from the Kernel API Manual, and today's main character is iio_write_channel_ext_info(9). she's an ext_info-writing girlie and she's about to eat, no cap ✨

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🌸 NAME 🌸

iio_write_channel_ext_info — write ext_info attribute from a given channel 💖

like. that's literally her whole job. write the ext_info attribute. from a given channel. periodt.

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🦋 SYNOPSIS 🦋

ssize_t iio_write_channel_ext_info (struct iio_channel *chan , const
char *attr , const char *buf , size_t len );

look at her signature. so clean. so iconic. four arguments and a ssize_t return, we love a consistent queen 👑

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✨ ARGUMENTS ✨

• chan — The channel being queried. 🫶 this is the channel bestie, the one we're doing the whole thing on
• attr — The ext_info attribute to read. 👀 yep, that's the attribute name you're pointing at
• buf — The new attribute value. Strings need to be zero-terminated, but the terminator should not be included in the len below. ⚠️ literally do not count the terminator in len, i'm begging
• len — The size of the new attribute value. 📏 just the size. that's it. that's the number

ngl the buf/len thing is the one place people fumble — zero-terminated string, yes; terminator counted in len, absolutely not 🙈

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💜 DESCRIPTION 💜

Returns the number of accepted bytes, which should be the same as len. 🔥

An error code can also be returned. 💀 so like… vibe check the return value before you celebrate, iykyk

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🌈 SEE ALSO 🌈

the whole friend group came out for this one, and we're listing every single one because nobody gets left behind 🫶

Kernel file ./include/linux/iio/consumer.h struct iio_channel(9), iio_channel_get(9), iio_channel_release(9), devm_iio_channel_get(9), iio_channel_get_all(9), iio_channel_release_all(9), devm_iio_channel_get_all(9), fwnode_iio_channel_get_by_name(9), devm_fwnode_iio_channel_get_by_name(9), iio_channel_get_all_cb(9), iio_channel_cb_set_buffer_watermark(9), iio_channel_release_all_cb(9), iio_channel_start_all_cb(9), iio_channel_stop_all_cb(9), iio_channel_cb_get_channels(9), iio_channel_cb_get_iio_dev(9), iio_read_channel_raw(9), iio_read_channel_average_raw(9), iio_read_channel_processed(9), iio_read_channel_processed_scale(9), iio_write_channel_attribute(9), iio_read_channel_attribute(9), iio_write_channel_raw(9), iio_read_max_channel_raw(9), iio_read_min_channel_raw(9), iio_read_avail_channel_raw(9), iio_read_avail_channel_attribute(9), iio_get_channel_type(9), iio_read_channel_offset(9), iio_read_channel_scale(9), iio_multiply_value(9), iio_convert_raw_to_processed(9), iio_get_channel_ext_info_count(9), iio_read_channel_ext_info(9), iio_read_channel_label(9)

that's the squad. all thirty-something of them. memorize it, it's giving study group 🌸

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mwah 💋 that's the whole page, go write some ext_info attributes bestie, you're gonna slay 🧚

signing off from ./include/linux/iio — October 2026, Kernel API Manual, iio_write_channel_ext_info(9) — catch you in the next manpage 💜✨