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Comment by rsync | Hacker News Reader

This is a problem I used to solve with 'zmodem' which you can install on both ends and use to perform text transfers, solely over the interactive channel.

I think the binaries were named 'zs' and 'zr'. It's been a long time since I needed to do this anywhere...

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You're close on the names of the binaries. They're 'sz' and 'rz'.

I used the crap out of them dialing-in to systems back in the day. I had TELNET and FTP access to the Internet out of a dial-in to a shell on a Unix host in the mid 90s (no SLIP, PPP, or SLiRP from the provider at the time. It was great to be able to ftp down files to my home directory then 'sz' them back home.

I wish terminal emulators still supported zmodem natively like some of the better emulators many years ago. It's not too difficult to configure iTerm2 to invoke rz when detecting the escape sequence[1], but it's still too much friction. sz/rz is something I would be using everyday, but I prefer sticking to Terminal.app on macOS--I prefer zero-config environments because of all the various systems, local and remote, I interact with on a daily basis.

scp and sftp are great, but the nice thing about in-band file transfers is that your shell session already has the current context for simplifying the transfer. For example, you often want to send to or receive from the current working directory, or something nearby, and interactive file globbing is just a single tab key away, without having to switch sessions, login all over again, copy paths, etc.

[1] I don't miss automatic printing without confirmation, though. The prank of `cat /vmlinuz | write user` wasn't that funny when the service desk hands you an entire ream of garbage along with a reprimand.

Gnu screen supports zmodem send and receive. I use it frequently to get files into old retro computers I’m playing with.

I’ve used it in datacenters where I’m ssh’d through three intermediate hosts, or when I’m inception-ing down into containers and vm’s

Tweeted about zmodem just last night! https://twitter.com/ryancnelson/status/1306444057602711553

Based on an offhand comment at https://www.extraputty.com/features/zmodem.html, they were `sz` and `rz`.

Wikipedia (https://en.wikipedia.org/wiki/ZMODEM) says that this came out of the BBS days. Boy, that takes me back.

Zmodem, xmodem, kermit. Don't know which one's better etc.

Last time I used one of these (don't remember which) was when my ISP booted me off cause of not paying bill, but minicom still worked, and gave me a shell. This was around 2005.

zmodem was the most advanced in terms of both efficiency and ability to resume broken transfers ...

IIRC smodem was superior (but maybe not so common): https://en.wikipedia.org/wiki/SMODEM

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