Install zssh with Homebrew

Project links

• Homepage

Commands and aliases

• zssh
• ztelnet

Project history

The project was registered on SourceForge on 2000-06-27 and is credited on the homepage to Matthieu Lucotte. Its public homepage and SourceForge page describe zssh as Zmodem SSH: a way to transfer files to or from a remote machine while staying inside an already-authenticated secure shell session.

zssh's design reflects an older Unix remote-login workflow. Instead of opening a second terminal and running scp, it inserts a tty/pty layer between the user and local ssh process, then switches that channel between normal shell mode and local file-transfer commands after an escape sequence.

Adoption history

zssh never became a replacement for scp, sftp, or rsync, but it remained packaged because it solved a specific interactive problem: moving files during a live remote shell session when re-authentication or another connection was inconvenient.

Its continued presence in package systems is a classic preservation case for small Unix tools: the upstream release is old, the protocol it depends on is older still, but a narrow workflow still exists for users who know exactly why they want ZMODEM over an SSH terminal.

How it is used

A user starts zssh much like ssh. During the remote shell session, pressing the configured escape sequence opens zssh's local prompt, where builtins such as rz and sz hook local transfer programs into the SSH channel. The FAQ emphasizes that ssh, sz, and rz must be available, with rz/sz required on both local and remote machines.

The practical failure modes are terminal-oriented: escape-key conflicts, non-8-bit-clean pty chains, incompatible rz/sz versions, and programs such as remote screen sessions interfering with the transparent channel.

Why package nerds care

zssh matters to package nerds as a fossil of a transitional era between dial-up/BBS-style ZMODEM habits and modern encrypted remote administration. It packages an old terminal file-transfer protocol as a composable Unix wrapper around ssh.

It is also a reminder that packaging sometimes preserves workflows rather than fashionable software: a tiny C program, readline-style local prompt, and external rz/sz dependency can remain useful long after the upstream website stops looking modern.

Timeline

• 2000-06-27: zssh project registered on SourceForge.
• 2003-09-24: zssh 1.5c listed as the latest release on the project homepage.
• 2013-03-21: SourceForge project page records the last project update.

Related projects

• Related tools and protocols include OpenSSH, telnet, scp, sftp, rsync, lrzsz, rz, sz, and the ZMODEM protocol.

Sources

• https://sourceforge.net/projects/zssh/
• https://zssh.sourceforge.net/
• https://zssh.sourceforge.net/FAQ