memchan(n)

💖 memchan — the manual, but make it cute 💖

okay bestie, buckle up, we're talking about memchan (section n of the manual, if you're keeping score) — Create and manipulate memory channels. yes it's giving "what even is a memory channel" and yes I will explain. 🫶

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✨ SYNOPSIS ✨

package require Tcl
package require memchan
memchan ?-initial-size len?

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🌸 DESCRIPTION 🌸

so this one page is doing double duty, no cap — it documents both the whole package and the command memchan itself. main character energy fr.

The package hands you a bunch of in-memory channels, and you can use them to:

• capture stream-like information in a natural way instead of using set and append to manipulate strings (like... why would you do that to yourself bestie 😭)
• or to transfer data between interpreters, whether they're in the same thread or not.

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👑 COMMAND 👑

memchan ?-initial-size len?

This creates a chunk-oriented in-memory channel and returns its handle. slay. 💅

If you specify an initial size, the system will pre-allocate len bytes of buffer space for the contents. And no, that is not a restriction on the ultimate size of the channel — it will always grow as much as is necessary to accommodate the data written into it. it's flexible like that. ✨

⚠️ real talk though: the channels created here can be transferred between interpreters in the same thread and between threads, but only as a whole. It is not possible to use them to create a bi- or unidirectional connection between two interpreters. periodt.

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🎀 the read-only options 🎀

Memory channels created by memchan provide two read-only options which you can query via the standard fconfigure command. They are:

• -length — the value of this option is the number of bytes currently stored in the queried memory channel.
• -allocated — the value of this option is the number of bytes currently allocated by the queried memory channel. This number is at least as big as the value of -length.

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🦋 fileevent tea 🦋

Since the channels generated by memchan grow as necessary, they are always writable. Which means... a writable fileevent-handler will fire continuously. yeah. constantly. it's a lot. 😭

The channels are also readable if they contain more than zero bytes and the seek location is not at the end of the channel. Under these conditions a readable fileevent-handler will fire continuously too. 💀

🙈 heads up bestie: writing to such a channel usually occurs at the end, thus suppressing readable events. This also means that users have to take care to seek the channel to a location before the end before trying to read data back. don't skip that step, I'm begging.

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🌈 SEE ALSO 🌈

fifo, fifo2, null, random, zero

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⭐ KEYWORDS ⭐

channel, chunk, i/o, in-memory channel, memchan

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💜 COPYRIGHT 💜

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

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okay that's the whole thing, you ate that. 💅✨ This was Memory channels, version 2.2, and it lives at memchan(n) — thanks for reading my TED talk, ily, go write some channels 🫶🎀🦋