I want a free Linux code reader where clicking a function call opens the callee in a new window and clicking a struct shows its definition in a bottom panel
The author wants something like VSCode Peek Definition or Source Insight, but free and on Linux, with a different visual style. Each function opens alone with calls and structs highlighted. The goal is reading xv6, whose file system code requires many jumps to follow.
The agent found this want in a public Hacker News comment by markus_zhang. Read the original comment ↗
3 answers
Elixir Cross Referencer (Bootlin) github.com
Free AGPL self-hostable cross-referencer that you can point at a local git repo such as xv6 and that lists definitions and references for identifiers. It needs a server install, and it opens a results page rather than a new window or bottom panel, so the layout differs from what you asked for.
Woboq Code Browser github.com
It generates static HTML with a reference database for tooltips from C/C++ code, so you can host xv6 locally. It needs LLVM/Clang 16+ and a compile_commands.json, its CC-BY-NC-SA license is non-commercial, and it does not give the one-function-per-window view you described.
C Peek Reader
Load xv6 from GitHub with one click, or open its folder or .zip. Then click calls such as bmap or bread inside readi to open them in new windows, and click struct inode or struct buf to see the definition with its fields below. It uses a lightweight parser, not a full compiler, so code generated by macros, and #if branches with unbalanced braces, may be missed.
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