Activates buffer-update events on a channel, or as Lua callbacks.

Example (Lua): capture buffer updates in a global events variable (use "print(vim.inspect(events))" to see its contents): >lua events = {} vim.api.nvim_buf_attach(0, false, { on_lines=function(...) table.insert(events, {...}) end}) <

Parameters:

• {buffer} Buffer handle, or 0 for current buffer

• {send_buffer} True if the initial notification should contain the whole buffer: first notification will be nvim_buf_lines_event. Else the first notification will be nvim_buf_changedtick_event. Not for Lua callbacks.

• {opts} Optional parameters. - on_lines: Lua callback invoked on change. Return true to detach. Args: - the string "lines" - buffer handle - b:changedtick - first line that changed (zero-indexed) - last line that was changed - last line in the updated range - byte count of previous contents - deleted_codepoints (if utf_sizes is true) - deleted_codeunits (if utf_sizes is true)

             - on_bytes: lua callback invoked on change. This
               callback receives more granular information about the
               change compared to on_lines. Return `true` to detach. Args:
               - the string "bytes"
               - buffer handle
               - b:changedtick
               - start row of the changed text (zero-indexed)
               - start column of the changed text
               - byte offset of the changed text (from the start of
                 the buffer)
               - old end row of the changed text
               - old end column of the changed text
               - old end byte length of the changed text
               - new end row of the changed text
               - new end column of the changed text
               - new end byte length of the changed text
  
             - on_changedtick: Lua callback invoked on changedtick
               increment without text change. Args:
               - the string "changedtick"
               - buffer handle
               - b:changedtick
  
             - on_detach: Lua callback invoked on detach. Args:
               - the string "detach"
               - buffer handle
  
             - on_reload: Lua callback invoked on reload. The entire
               buffer content should be considered changed. Args:
               - the string "reload"
               - buffer handle
  
             - utf_sizes: include UTF-32 and UTF-16 size of the
               replaced region, as args to `on_lines`.
             - preview: also attach to command preview (i.e.
               'inccommand') events.
  

Return: False if attach failed (invalid parameter, or buffer isn't loaded); otherwise True. TODO: LUA_API_NO_EVAL

See also:

• nvim_buf_detach()
• api-buffer-updates-lua