osc52-copy

Copy text to the local clipboard from anywhere using the OSC 52 terminal escape sequence. Works over SSH without X11/Wayland forwarding.

Usage

echo hello | osc52-copy
osc52-copy "some text"

Installation

Drop the script somewhere on your $PATH and make it executable:

install -m 755 osc52-copy ~/.local/bin/

Requirements

• A terminal emulator that supports OSC 52 (iTerm2, kitty, WezTerm, recent xterm, Alacritty with terminal.osc52 enabled, etc.).
• Standard tools: bash, base64, tr, printf.

Inside tmux

tmux must be configured to forward the sequence to the outer terminal. The script supports either of:

set -g set-clipboard on        # preferred; 'external' also works
set -g allow-passthrough on    # alternative

If neither is set, the script prints a warning to stderr explaining how to fix it. With set-clipboard, the script sends a raw OSC 52 sequence. With allow-passthrough, it wraps the sequence in tmux's DCS passthrough envelope.

How it works

OSC 52 lets a program tell the terminal "put this base64-encoded text in the clipboard." The script:

1. Reads input from stdin or arguments.
2. Base64-encodes it (newlines stripped, since OSC sequences cannot contain them).
3. Wraps it as ESC ] 52 ; c ; <base64> BEL (c selects the system clipboard).
4. Inside tmux, queries set-clipboard and allow-passthrough to pick the right delivery: raw OSC 52 (set-clipboard) or DCS-wrapped (allow-passthrough).
5. Writes the sequence to /dev/tty so it works even when stdout is piped or redirected.

Why not theimpostor/osc?

osc is a more featureful Go tool (paste, multiple clipboard targets, tty override). osc52-copy is a few lines of bash that fits into dotfiles without an extra binary install.