uart_xmit_advance(9)

💖 uart_xmit_advance — a Kernel API Manual moment ✨

okay bestie, so this is a page from the Kernel API Manual, and it's literally about uart_xmit_advance. yes that's a mouthful, no I will not be shortening it, we respect her full name 💅

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🌸 NAME 🌸

uart_xmit_advance — advance the xmit buffer and account for the chars you just Tx'ed, periodt 🎀

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🦋 SYNOPSIS 🦋

void uart_xmit_advance (struct uart_port *up , unsigned int chars );

that's the whole vibe check right there, no cap 💜

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✨ ARGUMENTS ✨

• up — the uart_port structure that describes the port. she's the main character of this whole operation 👑
• chars — the number of characters sent. like, actually sent. keep track, bestie 🍓

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🔥 DESCRIPTION 🔥

so what does she do? this function advances the tail of the circular xmit buffer by the number of chars transmitted — literally just nudging the tail forward by however many chars went out 🧚

and she also handles the accounting of transmitted bytes, which get tracked into up's icount.tx. so like, not only does she move the buffer along, she keeps the receipts. obsessed 💖

ngl it's giving "quietly doing two jobs at once and never complaining" energy. icon behavior fr fr ✨

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🌈 SEE ALSO 🌈

okay this is the friend group, everybody say hi 💅✨

• Kernel file ./include/linux/serial_core.h struct uart_ops(9)
• uart_port_set_cons(9)
• uart_port_lock(9)
• uart_port_lock_irq(9)
• uart_port_lock_irqsave(9)
• uart_port_trylock(9)
• uart_port_trylock_irqsave(9)
• uart_port_unlock(9)
• uart_port_unlock_irq(9)
• uart_port_unlock_irqrestore(9)
• enum uart_pm_state(9)
• enum UART_TX_FLAGS(9)
• uart_port_tx_limited(9)
• uart_port_tx_limited_flags(9)
• uart_port_tx(9)
• uart_port_tx_flags(9)

like I said. big friend group. all iconic, all linked above 👆🫶

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💀 reminder bestie: this is kernel API territory, so treat the buffer math with respect — she's advancing real state, not vibes 🌸

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mwah, that's the page!! sourced straight from ./include/linux, dated October 2026, and brought to you by the uart_xmit_advance(9) girlies 🎀💖 see u in the next manpage, bestie ✨🦋