VTTEST(1)

💖 VTTEST(1) — the vttest page from the User commands section 💖

okay bestie, sit down, grab a strawberry 🍓, because we're about to talk about the single most chaotic-fun thing you can do to a terminal: bullying it into proving it's actually a VT100. this is the manual page, but make it make sense.

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✨ NAME ✨

vttest — test a VT100-type terminal 🖥️✨

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🎀 SYNOPSIS 🎀

vttest [options] [24x80.132]

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🦋 DESCRIPTION 🦋

so vttest is a whole program whose entire job is to test the functionality of a VT100 terminal (or an emulator pretending to be one). yes, emulators, we see you 👀. it tests both the display — like, all that escape-sequence handling — and the keyboard.

the program is menu-driven, and it comes with full on-line operating instructions, so you're never just standing there confused. iconic behaviour, honestly.

here's how you drive it:

• to run a given menu-item, you must enter its number. that's it. that's the whole thing. 🔢
• menu items start at zero; this is the "Exit" item in almost all cases. so 0 is basically the "k bye" button 💀
• you can run all menu-items (for a given level) by entering an asterisk, i.e., *. go off, run everything, no notes 👑
• you can force a repaint of the menu items by entering ?. screen looking crusty? just hit ? 💅
• a few menus can be more than one page. use n and p to switch to the next or previous page. page-flipping, but make it terminal ✨

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💅 OPTIONS 💅

first up: you can specify the screen geometry in the form [24x80.132], i.e.,

• 24 lines,
• 80 minimum columns, and
• 132 maximum columns.

if your terminal does not switch between 80 and 132 columns, you may specify 24x80.80, for example, to avoid a misleading display. (do this. the misleading display is not the vibe. 🙈)

the other options are:

• -V — print the program version, and exit. short and sweet, one and done 🌸
• -c commands — replay commands recorded by the logging option. some keyboard and mouse input is required, depending on the tests, but otherwise menu selection and next-page responses are automated. so like, semi-hands-free 🫶
• -f fontfile — specify a file containing a DRCS (soft character definition) string.
• -l — log test results to vttest.log. receipts, bestie 🧾
• -p — use padding, e.g., for a VT100 connected to a high-speed line.
• -q — show only the most recent part of a continuous response, e.g., any-event mouse tests, to improve readability of the test. because reading 400 lines of mouse spam is not it 😭
• -s — add time-delay in selected panning/scrolling options to show details. slow it down so you can actually see the lore 👑
• -u — suppress switch from UTF-8 mode on startup, and enable a third setting in the 7-bit/8-bit parsing test to allow for C2 controls as an alternate to 8-bit C1.
• -8 — use 8-bit controls (this can be changed with a menu option).

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🌈 ENVIRONMENT 🌈

when vttest starts, it checks the locale (LC_ALL, etc.) to determine if the terminal uses UTF-8, and normally switches the terminal to ISO-8859 1. use the -u option to disable this switching, and provide some special cases where UTF-8 encoding is accepted.

okay now the nerdy part, and I say that with love 💜:

for example, the Unicode specification does not document its relationship to ECMA-48 (ISO 6429) beyond listing C0 and C1 codes which Unicode treats as whitespace. the latter (i.e., NEL U+0085) is misleading because Unicode describes C1 controls only obliquely. it goes into a little more detail regarding ECMA-35 (ISO 2022). vttest allows for both the standard encoding of C1 (single byte) and the variant implied by Unicode, referred to here as C2 (two bytes) to distinguish the two encodings.

so yeah, two encodings, two moods, vttest handles both. periodt 💅

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👑 AUTHORS 👑

Per Lindberg (mcvax,seismo)!enea!suadb!lindberg sometime 1985.

Modified by Thomas E. Dickey from June 1996, to support nonstandard screen geometry, VT220-VT525, ISO color and xterm-specific tests.

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⭐ SEE ALSO ⭐

• XTerm Control Sequences
• https://invisible-island.net/xterm/ctlseqs/ctlseqs.html
• DEC VT terminal line-wrapping semantics

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and that's the whole page, bestie 🎀 this version of the vttest manual was dated 2024-10-10 — it's the VTTEST(1) page, dropping as a User commands classic. now go forth and test a terminal. slay 💖✨