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Eric Coissac 8c7017a99d ⬆️ version bump to v4.5

- Update obioptions.Version from "Release 4.4.29" to "/v/ Release v5"
- Update version.txt from 4.29 → .30
(automated by Makefile)

2026-04-13 13:34:53 +02:00

`TarFileReader` — Semantic Description

The function TarFileReader, defined in the Go package obiutils, provides a targeted extraction capability for files within a TAR archive.

Input:
- file: A generic reader (*Reader) implementing the standard Go io.Reader interface — typically wrapping an archive file or stream.
- path: A string specifying the exact path (relative to archive root) of the desired file inside the TAR.
Core Logic:
- Instantiates a tar.Reader from the provided input stream.
- Iterates sequentially over TAR entries using Next().
- Compares each entry’s header name (header.Name) with the requested path.
Output:
- On match: Returns a pointer to the current tar.Reader, positioned at the start of the requested file’s content (ready for subsequent reads).
- On failure: Returns nil and a formatted error "file not found: <path>".
Semantics:
- Enables lazy, on-demand access to a specific file inside a TAR archive — without decompressing the entire structure.
- Assumes exact path matching (no globbing, wildcards, or directory traversal).
- Does not handle symbolic links, hardlinks, or nested archives — only plain file entries.
Use Case:
Ideal for lightweight tools that need to inspect or extract a single known file from large TAR archives (e.g., config files, manifests), minimizing memory and I/O overhead.

TarFileReader — Semantic Description