steve [ ~/build/emacs-26/src ]$ ./emacs
redisplay_preserve_echo_area (2)
redisplay_internal 0
0x1314c30 (manual): same window start
0x1314c30 (manual): 1
redisplay_internal 0
redisplay_preserve_echo_area (8)
redisplay_internal 0
redisplay_preserve_echo_area (8)
redisplay_internal 0
redisplay_internal 0
0x1314c30 (R-lang.pdf): same window start
0x1314c30 (R-lang.pdf): 1
redisplay_preserve_echo_area (8)
redisplay_internal 0
redisplay_preserve_echo_area (8)
redisplay_internal 0
redisplay_preserve_echo_area (8)
redisplay_internal 0
redisplay_preserve_echo_area (12)
redisplay_internal 0
redisplay_preserve_echo_area (9)
redisplay_internal 0
redisplay_internal 0
redisplay_preserve_echo_area (12)
redisplay_internal 0
redisplay_preserve_echo_area (9)
redisplay_internal 0
redisplay_internal 0
redisplay_preserve_echo_area (12)
redisplay_internal 0
redisplay_preserve_echo_area (9)
redisplay_internal 0
redisplay_internal 0
redisplay_preserve_echo_area (12)
redisplay_internal 0
redisplay_preserve_echo_area (9)
redisplay_internal 0
redisplay_internal 0
redisplay_preserve_echo_area (12)
redisplay_internal 0
redisplay_preserve_echo_area (9)
redisplay_internal 0
redisplay_internal 0
redisplay_preserve_echo_area (12)
redisplay_internal 0
redisplay_preserve_echo_area (9)
redisplay_internal 0
redisplay_internal 0
redisplay_preserve_echo_area (12)
redisplay_internal 0
redisplay_preserve_echo_area (9)
redisplay_internal 0
redisplay_internal 0
redisplay_preserve_echo_area (12)
redisplay_internal 0
redisplay_preserve_echo_area (9)
redisplay_internal 0
redisplay_internal 0
redisplay_preserve_echo_area (12)
redisplay_internal 0
redisplay_preserve_echo_area (9)
redisplay_internal 0
redisplay_internal 0
redisplay_internal 0
redisplay_preserve_echo_area (8)
redisplay_internal 0
steve [ ~/build/emacs-26/src ]$