Which comes first in DOS timestamps, the date or the time?

There are a lot of old DOS-centric file formats, especially file archiving and compression formats, which store timestamps of files. Most of them use the standard MS-DOS timestamp format for such things. This format is usually interpreted as two 16-bit integers: one for the date, and one for the time of day. I'm not sure, … Continue reading Which comes first in DOS timestamps, the date or the time?

How to vote in a late-stage two-party system

No voting system is perfect, but one of the worst systems that is even remotely compatible with democracy is the one known as first-past-the-post. In the simplest form of this system, each voter gets one vote per contest. A contest may have more than two candidates. The candidate with the most votes wins, even if … Continue reading How to vote in a late-stage two-party system

Notes on some old self-extracting ZIP archives

The old PKZIP compression software for DOS includes a utility named "ZIP2EXE", which turns a plain ZIP file into a self-extracting executable file in DOS EXE format. Depending on the version of PKZIP/ZIP2EXE, and the options used, there are several different ways in which this EXE file is constructed. I wanted to learn about these … Continue reading Notes on some old self-extracting ZIP archives

What is LZSS compression?

I'm not asking how to implement LZSS. I'm asking how to distinguish things-that-are-LZSS from things-that-are-not-LZSS. It's generally understood that LZSS is a kind of data compression. It's supposedly a derivative of LZ77. But you may struggle to find out anything definitive or verifiable about LZSS. The name LZSS is more than likely derived from Lempel–Ziv–Storer–Szymanski, … Continue reading What is LZSS compression?

Survey of LHarc and LHA versions and names

[See this post for some updates to the information here.] The LHarc family of software (including LHA, etc.) is an old compression and archiving utility, originally for DOS computers. I've found the LHarc version history to be confusing in a number of ways. In this post, I'll try to explain what's what, to the best … Continue reading Survey of LHarc and LHA versions and names