About TobsCore, a team writing tested C, Git, Vim and Linux notes

What the site covers

The notes fall into five areas:

• C and networking: sockets, byte order, the bits of a floating point number.
• Git: everyday commands, the cases where they surprise you, and practice material such as Githug.
• Vim: modes, motions, a short .vimrc, and how to leave the editor.
• The Linux command line: GPG encryption, SSH configuration, tar archives.
• WordPress: the Romangie theme, read through its code and its current listing on wordpress.org.

Readers are assumed to use a terminal already. What they usually want is the exact command, the output it prints and the reason it behaves that way.

How examples are tested

Every code listing was compiled or run before publication. When a listing prints something, the output below it is what that run printed, compiler warnings included, and nothing in a code block is typed from memory.

Near the top of each guide, a tested line names the compiler and its version, the operating system and, where it matters, library versions and flags. A typical one reads "gcc 14.4.0 on Debian 13.7 (glibc 2.41)". If an example behaves differently on your machine, compare against that line first. An older distribution, another libc or a macOS toolchain explains most differences.

Defaults, limits and counts get the same treatment: they are looked up in the man page or the source code of the version in the tested line.

How pages are updated

A revised guide shows an "updated" date next to its publication date, and its tested line moves to the versions used for the revision. Fixing a single wrong command or output works the same way, with the correction made in place and a new date. A page never gets a new date without a change to its content.

Reporting an error

Maybe a command fails, an output does not match or a statement is plain wrong. The contact page lists what a useful report contains, and confirmed errors are corrected on the page itself.

The tools and the game

Four small programs run entirely in your browser:

• The IEEE 754 converter shows the sign, exponent and mantissa bits of a float or double, and each bit can be flipped with a click.
• The byte order converter lays an integer out byte by byte on little-endian and big-endian machines and shows what htons() and htonl() do to it.
• The SSH config generator inside the SSH config alias guide turns a host, a user and a port into a ready Host block.
• The Vim trainer is a 30-second game for practicing h, j, k and l.

Ads, sponsors and tracking

There is no advertising. Pages set no cookies, run no analytics or tracking scripts and embed nothing from other servers, and the fonts are served from the same machine as the pages. The privacy policy covers what the web server does record.

Who writes

The TobsCore editors write the site and read [email protected]. The AI notice explains where AI tools come into research, drafting and images.

The Linux guides do not assume a particular distribution. Where one depends on a distribution-specific path, it says so at the spot where the path appears.