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Understanding Linux – The Kernel Perspective

@unix-byte.bsky.social

Book "Understanding Linux: The Kernel Perspective" leanpub.com/linuxkernel Amazon: amazon.com/dp/B0FCBKCGGC #linux #unix #freebsd #operatingsystems #kernelmodules

Posts Replies Media

Understanding Linux – The Kernel Perspective @unix-byte.bsky.social · 12/08/2025

This was bound to happen. Greed always wins in the long term, and especially at Microsoft

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Understanding Linux – The Kernel Perspective @unix-byte.bsky.social · 30/07/2025

If nd->last_type != LAST_NORM, it means nd->last_type is either LAST_DOT (for ".") or LAST_DOTDOT (for "..")

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Understanding Linux – The Kernel Perspective @unix-byte.bsky.social · 30/07/2025

When a process invokes a system call referencing a pathname (e.g., "foo/bar/baz"), the kernel calls walk_component() on each component of the path: "foo" → "bar" → "baz". If a component is either "." or "..", walk_component() dispatches handling to handle_dots()

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Understanding Linux – The Kernel Perspective @unix-byte.bsky.social · 30/07/2025

Where is it defined that "." denotes the current working directory? Does the C language understand this convention? The answer is no—for example, C's chdir() function simply passes the string to the chdir system call. It is the kernel that interprets "." as the current working directory

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Understanding Linux – The Kernel Perspective @unix-byte.bsky.social · 29/07/2025

Of the four parts mentioned—the shell, programs, terminal emulator, and TTY driver—the first three are userland processes, while the TTY driver is part of the kernel. The userland processes interact with the TTY driver through system calls and device interfaces.

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Understanding Linux – The Kernel Perspective @unix-byte.bsky.social · 29/07/2025

Where’s the kernel? In this great zine by Julia Evans the kernel isn’t shown—but the TTY driver is part of it, managing I/O between the terminal and user-space programs—like the shell—and terminal devices. The zine focuses on what the user can see 👀

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Understanding Linux – The Kernel Perspective @unix-byte.bsky.social · 28/07/2025

Of the four parts mentioned by @b0rk.jvns.ca—the shell, programs, terminal emulator, and TTY driver—the first three are userland processes, while the TTY driver is part of the kernel. The userland processes interact with the TTY driver through system calls and device interfaces.

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Understanding Linux – The Kernel Perspective @unix-byte.bsky.social · 28/07/2025

Where’s the kernel? In this great zine by @b0rk.jvns.ca the kernel isn’t shown—but the TTY driver is part of it, managing I/O between the terminal and user-space programs—like the shell—and terminal devices. The zine focuses on what the user can see 👀 bsky.app/profile/b0rk...

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Understanding Linux – The Kernel Perspective @unix-byte.bsky.social · 27/07/2025

@unix-byte.bsky.social

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