LC_CHANNE..._OVERHEAD(3)

💖 LC_CHANNE..._OVERHEAD(3) — aka the "how many extra packets are we yeeting" page 💖

okay so bestie, welcome to the Librecast Programmer's Manual 🦋 (that's the manual name, it lives up here at the top, consider it folded in and living its best life ✨). Today's episode: how many overhead packets your RaptorQ setup is gonna send. Buckle up, it's giving very specific and very important. 🎀

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✨ NAME ✨

lc_ctx_coding_set, lc_channel_rq_overhead — set Librecast RaptorQ overhead packets.

ngl, the NAME line says lc_ctx_coding_set while the SYNOPSIS down there says lc_ctx_rq_overhead 👀 — we're just reporting what's on the page, no editing, no fixing, that's the rule. 💅

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📚 LIBRARY 📚

Librecast library (liblibrecast, -llibrecast). That's the one, that's the vibe. 🫶

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🌈 SYNOPSIS 🌈

#include <librecast/net.h>

int lc_ctx_rq_overhead(lc_ctx_t *ctx, int overhead);
int lc_channel_rq_overhead(lc_channel_t *chan, int overhead);

Compile and link with -llibrecast. Don't forget it, it will simply not work and you will simply cry 😭

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💅 DESCRIPTION 💅

so here's the tea, two whole functions, both obsessed with overhead:

• lc_ctx_rq_overhead() — sets the default overhead packets for channels that get created subsequently using the context ctx. Like, it's setting the vibe for all the babies that come after 🐣
• lc_channel_rq_overhead() — sets RaptorQ overhead packets for a Librecast channel, chan, and it overrides any defaults it inherited from the parent Librecast context. main character energy, honestly 👑

chan is a pointer to a Librecast channel. yes, a pointer. yes, you have to deal with that. ✨

the overhead argument is the number of overhead packets to send in a single call to lc_channel_send(3) or lc_channel_sendmsg(3). the way that one number controls so much...

• if overhead is >= 0, then a single call to a sending function with LC_CODE_FEC_RQ enabled will cause K' + overhead packets to be sent. slay 💖
• if overhead is < 0, then no automatic sending will occur. periodt. nothing goes out automatically, that's the whole rule 🙈

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🎀 RETURN VALUE 🎀

Returns the new overhead value. that's it, that's the return. short and iconic 💫

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💀 ERRORS 💀

None. literally none. a flawless, error-free queen. 👑

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🔥 SEE ALSO 🔥

• lc_channel_new(3)
• lc_channel_close(3)
• lc_channel_send(3)
• lc_channel_sendmsg(3)
• lc_channel_set_sym_key(3)
• lc_ctx_new(3)
• lc_socket_setopt(3)
• lc_socket_recv(3)

go read those too, bestie, iykyk 📖✨

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and that's a wrap!! this whole page is brought to you by LIBRECAST, dated 2025-03-24 🌸 — and yes the footer also says LC_CHANNE..._OVERHEAD(3) again because it's extra like that 💅 mwah, go forth and set your overhead 💖🦋🧚