SIGNALS.txt for Tux Paint

Tux Paint - A simple drawing program for children.

Copyright 2019 by Bill Kendrick and others
bill@newbreedsoftware.com
http://www.tuxpaint.org/

April 3, 2019

Tux Paint responds to the following signals (which can be
sent to the program's process via `kill` or `killall`, for
example).

 * SIGTERM (also, [Ctrl]+[C] from a terminal running "tuxpaint")

   Tux Paint responds as if the "Quit" button were pressed,
   or the desktop environment was told to close Tux Paint
   (e.g., by clicking a window close button, or pressing
   [Alt]+[F4] on most systems).

   From the main interface, Tux Paint will prompt whether or
   not you wish to quit, and (unless overridden by "--autosave")
   if you'd like to save the current drawing (if unsaved),
   and if so, and it's a modified version of an existing drawing
   (unless overridden by "--saveover" or "--saveovernew"),
   whether or not to overwrite the existing drawing, or save
   to a new file.

   From other parts of the interface, the signal is currently
   interpreted as a request to go back (e.g., from the
   "New" dialog back to the main interface), as if a "Back"
   button in Tux Paint were clicked, or the [Esc] key pressed.

 * SIGUSR1 & SIGUSR2

   Tux Paint responds by setting its "--autosave" option, and either
   "--saveovernew" (for SIGUSR1) or "--saveover" (for SIGUSR2),
   and sending itself a SIGTERM signal.

   So, from the main interface, Tux Paint should quit almost immediately,
   with no questions asked.

   From other parts of the interface, unfortunately, Tux Paint
   will go back one level in the interface.  Therefore, at this time,
   it may be necessary to send this signal to Tux Paint a few times,
   for it to quit completely.

   e.g., `killall -s SIGUSR1 tuxpaint`

