STRUCT FW_CDEV_SEND_STREAM_PACKET(9)

🌸 struct fw_cdev_send_stream_packet(9) 🌸

okay bestie, welcome to the Kernel API Manual entry for struct fw_cdev_send_stream_packet — and yes, that's a whole mouthful, but trust me, it slaps 💅

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✨ NAME ✨

struct fw_cdev_send_stream_packet — send an asynchronous stream packet 🦋

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💖 SYNOPSIS 💖

struct fw_cdev_send_stream_packet {
    __u32 length;
    __u32 tag;
    __u32 channel;
    __u32 sy;
    __u64 closure;
    __u64 data;
    __u32 generation;
    __u32 speed;
 };

like, look at her. gorgeous. iconic. eight fields of pure potential 💜

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🫶 MEMBERS 🫶

• length — the length of the outgoing payload, in bytes. it's giving "how much stuff am i actually sending" 🎀
• tag — the data format tag 🌸
• channel — the isochronous channel you're transmitting to ✨
• sy — the synchronization code ⭐
• closure — gets passed right back to userspace in the response event, so it's basically your little note-to-self 🫶
• data — a userspace pointer to the payload, no cap 💖
• generation — the bus generation where the packet is valid 🦋
• speed — the speed to transmit at 🔥

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💅 DESCRIPTION 💅

so the FW_CDEV_IOC_SEND_STREAM_PACKET ioctl sends an asynchronous stream packet to every device which is listening to the specified channel 🫶 it's a broadcast bestie situation, main character energy all around.

the kernel then writes either an fw_cdev_event_response event or an fw_cdev_event_response2 event, which tells you whether the transmission succeeded or failed 👑 so yeah, you will get your vibe check back.

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🦋 SEE ALSO 🦋

kernel file ./include/uapi/linux/firewire-cdev.h 🌈

• struct fw_cdev_event_common(9)
• struct fw_cdev_event_bus_reset(9)
• struct fw_cdev_event_response(9)
• struct fw_cdev_event_response2(9)
• struct fw_cdev_event_request(9)
• struct fw_cdev_event_request2(9)
• struct fw_cdev_event_request3(9)
• struct fw_cdev_event_iso_interrupt(9)
• struct fw_cdev_event_iso_interrupt_mc(9)
• struct fw_cdev_event_iso_resource(9)
• struct fw_cdev_event_phy_packet(9)
• struct fw_cdev_event_phy_packet2(9)
• union fw_cdev_event(9)
• struct fw_cdev_get_info(9)
• struct fw_cdev_send_request(9)
• struct fw_cdev_send_response(9)
• struct fw_cdev_allocate(9)
• struct fw_cdev_deallocate(9)
• struct fw_cdev_initiate_bus_reset(9)
• struct fw_cdev_add_descriptor(9)
• struct fw_cdev_remove_descriptor(9)
• struct fw_cdev_create_iso_context(9)
• struct fw_cdev_set_iso_channels(9)
• struct fw_cdev_iso_packet(9)
• struct fw_cdev_queue_iso(9)
• struct fw_cdev_start_iso(9)
• struct fw_cdev_stop_iso(9)
• struct fw_cdev_flush_iso(9)
• struct fw_cdev_get_cycle_timer(9)
• struct fw_cdev_get_cycle_timer2(9)
• struct fw_cdev_allocate_iso_resource(9)
• struct fw_cdev_send_phy_packet(9)
• struct fw_cdev_receive_phy_packets(9)

that's the whole group chat, fr fr 😭

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aaaand that's the page! this lil beauty lives in ./include/uapi/linux, dated October 2026 — go off, kernel docs, you ate 💖✨🎀