null(n)

📦 version 2.3, in fedora 43, fedora 44

✨ null(n) ✨

okay bestie, welcome to the null manual page 💖 this one lives in the memchan family, so it's all about channels, and it's short and sweet. buckle up 🎀

🌈 NAME 🌈

null — create and manipulate null channels 🕳️✨

🦋 SYNOPSIS 🦋

package require Tcl

package require memchan

null

💅 DESCRIPTION 💅

heads up, bestie: the command described right here is only available in a not-yet released version of the package. use the CVS to get the sources. no cap. 🫠

null creates a null channel, and a null channel literally absorbs everything you write into it. that's its whole thing. it's giving black hole but make it i/o 🕳️💖

Reading from it is not possible — or rather, it will always return zero bytes. so like, you can try, and it'll just hand you nothing. iconic behaviour tbh.

These channels are essentially Tcl-specific variants of the null device for unixoid operating systems (/dev/null). you know the vibe. 🫶

Transferring the generated channel between interpreters is possible but does not make much sense. like sure, you could, bestie, but why 😭

✨ OPTIONS ✨

Memory channels created by null provide one additional option to set or query. one. singular. the whole menu. 💅

  • -delay ?milliseconds? — okay so, a null channel is always writable and readable (the manpage really said that, we'll get to it 👀). this means that all fileevent-handlers will fire continuously. to avoid starvation of other event sources, the events raised by this channel type have a configurable delay. this option is set in milliseconds and defaults to 5. ⏱️✨

🫠 the plot twist 🫠

A null channel is always writable and never readable. yes bestie, the page says both things, we're just relaying the lore, don't shoot the messenger 💀

This means that:

  • a writable fileevent-handler will fire continuously 🔥
  • a readable fileevent-handler will never fire at all 🦋

The exception to that last one? only the destruction of the channel, which will cause the delivery of an eof event to a readable handler. so it's one final goodbye event, and then nothing. periodt. 😭💔

👑 SEE ALSO 👑

  • fifo
  • fifo2
  • memchan
  • random
  • zero

go read those too, bestie, they're the whole friend group 🌸

🎀 KEYWORDS 🎀

  • channel
  • i/o
  • in-memory channel
  • null

Copyright (c) 1996-2003 Andreas Kupries <andreas_kupries@users.sourceforge.net>

and that's the whole page, bestie!! 🫶✨ this was Memory channels version 2.2, null(n), and yeah — that footer date energy is giving vintage but the knowledge is timeless 💅📚 mwah, go forth and write into the void 🕳️💖

📦 where this page comes from