Schedule Command

SCHEDULE-ANY-COMMAND.md

Schedule any command

This small sh function allows to schedule a command to be executed at a specific time. I use it for scheduling Claude Code "Continue" text in my tmux session

schedule_command.sh

function schedule_command() {
  # Example usage:
  # 1. Schedule a command to run at 20:00 UTC in session "WORK" window 3, pane 1:
  #    schedule_command "WORK:3" 1 "20:00" "echo 'Daily backup starting'"
  #
  # 2. Schedule a database maintenance task at midnight UTC:
  #    schedule_command "DB:1" 0 "00:00" "pg_repack -d mydb -t large_table"
  #
  # 3. Schedule a reminder in the current session:
  #    schedule_command "$(tmux display-message -p '#{session_name}'):$(tmux display-message -p '#{window_index}')" "$(tmux display-message -p '#{pane_index}')" "15:30" "echo 'Time for the team meeting!'"

  session_window="$1"  # Format: "SESSION:WINDOW" (e.g., "KIRR:3")
  window_index="$2"    # The window index (e.g., 1, 2, 3, etc.)
  target_time="$3"     # Format: "HH:MM" in UTC (e.g., "20:00" or "00:00")
  command="$4"         # The command to execute

  # Get the pane ID for the specified window index
  pane_id=$(tmux list-panes -t "$session_window" | grep "^$window_index:" | awk '{print $1}' | sed 's/[^0-9%]//g')

  if [ -z "$pane_id" ]; then
    echo "Error: Could not find pane with index $window_index in $session_window"
    return 1
  fi

  # Get current time components in UTC
  current_hour=$(date -u +"%H")
  current_minute=$(date -u +"%M")
  current_second=$(date -u +"%S")
  current_date=$(date -u +"%Y-%m-%d")

  # Extract hours and minutes from target time
  target_hour=${target_time%:*}
  target_minute=${target_time#*:}

  # Calculate current and target time in seconds since midnight
  current_seconds_since_midnight=$(( 10#$current_hour * 3600 + 10#$current_minute * 60 + 10#$current_second ))
  target_seconds_since_midnight=$(( 10#$target_hour * 3600 + 10#$target_minute * 60 ))

  # Determine if the target time is today or tomorrow
  if (( current_seconds_since_midnight >= target_seconds_since_midnight )); then
    # If current time is past the target time, schedule for tomorrow
    # On macOS, use -v for date adjustment
    target_date=$(date -u -d "tomorrow" +"%Y-%m-%d")
    delay=$(( 86400 - current_seconds_since_midnight + target_seconds_since_midnight ))
  else
    # Schedule for today
    target_date="$current_date"
    delay=$(( target_seconds_since_midnight - current_seconds_since_midnight ))
  fi

  # Sleep for the calculated delay in seconds
  (sleep "$delay" && tmux send-keys -t "$pane_id" "$command" && tmux send-keys -t "$pane_id" ENTER) &

  echo "Command scheduled to run at $target_time UTC on $target_date (in $delay seconds) on pane $pane_id (window index $window_index)"
}