dotfiles/home/zsh/files/waypipe.zsh

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if [ -n "$REMOTE_PATH" ]; then
# Fresh `s <host>` connection: the initial working directory is handed over in
# REMOTE_PATH (an env var is the only channel that survives waypipe's command
# transport intact — shell grouping like `cd …; exec …` does not). cd into it,
# then unset so it does NOT leak to child shells: a lingering exported
# REMOTE_PATH is what made every new zellij pane jump back to this same path
# instead of inheriting the pane's own cwd.
[ -d "$REMOTE_PATH" ] && cd "$REMOTE_PATH"
unset REMOTE_PATH
fi
if [ -n "$PREVIOUS_SESSION_ID" ]; then
# Spawned as a new window/terminal for an existing remote session (by the
# niri/hyprland keybind). Inherit that session's working directory: find a
# live shell whose SSH_SESSION_ID (carried in its environment) matches and
# cd to its cwd. Then drop the hint so child shells don't keep jumping back.
_best_pid=0
_prev_cwd=""
for _environ in /proc/[0-9]*/environ; do
_pid=${_environ%/environ}
_pid=${_pid#/proc/}
# cat (not a < redirect) so unreadable/ptrace-protected environ files
# fail quietly into the pipe instead of raising a shell error.
if cat "$_environ" 2>/dev/null | tr '\0' '\n' | grep -Fxq "SSH_SESSION_ID=$PREVIOUS_SESSION_ID"; then
[ "$(cat /proc/$_pid/comm 2>/dev/null)" = zsh ] || continue
# SSH_SESSION_ID is exported, so transient `zsh -c …` subshells (prompt
# hooks, zellij helpers) inherit it too — but they aren't real session
# panes and often sit at /. Skip anything invoked in command mode; only
# interactive login/pane shells should count.
cat /proc/$_pid/cmdline 2>/dev/null | tr '\0' '\n' | grep -Fxq -- -c && continue
_c=$(readlink -e /proc/$_pid/cwd 2>/dev/null) || continue
# A login shell still sitting at / is a helper forked during startup
# (e.g. p10k) that never ran the REMOTE_PATH cd, not a shell the user
# works in. Real panes have always cd'd somewhere; skip root.
[ "$_c" = / ] && continue
if [ -n "$_c" ] && [ "$_pid" -gt "$_best_pid" ]; then
_best_pid=$_pid
_prev_cwd=$_c
fi
fi
done
[ -n "$_prev_cwd" ] && cd "$_prev_cwd"
unset _best_pid _prev_cwd _environ _pid _c PREVIOUS_SESSION_ID
fi
function run_waypipe() {
if [ -z "$1" ]; then
echo "usage: run_waypipe <host>" >&2
return 1
fi
local SSH_SESSION_ID=$RANDOM REMOTE_PATH
# Map the current path relative to $HOME so it resolves to the remote user's
# home even when the username differs (the remote shell expands $HOME while
# parsing the command below).
if [[ "$PWD" == "$HOME" || "$PWD" == "$HOME"/* ]]; then
REMOTE_PATH="\$HOME${PWD#$HOME}"
else
REMOTE_PATH="$PWD"
fi
# Hand off the initial cwd and session token as a plain `env VAR=val … zsh`
# argv. This must stay free of shell grouping/metacharacters: waypipe rejoins
# and re-splits the command on whitespace and runs the leading word as a
# program, so `env` (a real binary) works but `cd …; exec …` would not.
#
# SSH_SESSION_ID is placed in TWO environments on purpose:
# - the leading prefix exports it into the LOCAL waypipe/ssh process, where
# the niri/hyprland "duplicate window" keybind reads it out of
# /proc/<ssh-pid>/environ to learn which session to clone;
# - the `env SSH_SESSION_ID=…` sets it on the REMOTE zsh, where the scan
# block above locates this session's shells by matching it.
SSH_SESSION_ID=$SSH_SESSION_ID waypipe -n ssh -t "$1" env REMOTE_PATH=\"$REMOTE_PATH\" SSH_SESSION_ID=$SSH_SESSION_ID zsh --login
}
alias s='run_waypipe'