consider tput instead of TIOCGWINSZ?

https://github.com/prompt-toolkit/python-prompt-toolkit/blob/master/prompt_toolkit/output/vt100.py#L369 (_get_size) currently uses TIOCGWINSZ to get the terminal size

on the particular system i use, for some reason this fails to get the correct size

stty -a
speed 38400 baud; rows 0; columns 0; line = 0;
                  ~~~~~~~~~~~~~~~~~           
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>;
eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R;
werase = ^W; lnext = ^V; discard = ^O; min = 1; time = 0;
-parenb -parodd -cmspar cs8 -hupcl -cstopb cread -clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff
-iuclc -ixany -imaxbel -iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt
echoctl echoke -flusho -extproc

but asking tput gets the right answer

$ tput lines
36
$ tput cols
78

in python this can be done using

curses.setupterm()
rows = curses.tigetnum('lines')
columns = curses.tigetnum('cols')

i'm not sure if there are any downsides to this/situations where the former works and the latter doesn't but would you be interested in trying this approach instead (and/or as a fallback)

thanks,
david

Start in prompt_toolkit/output/vt100.py at _get_size and compare the current TIOCGWINSZ path with the reported curses.setupterm(), tigetnum('lines'), and tigetnum('cols') approach. Check how each behaves on terminals reporting zero rows and columns; done means _get_size returns the correct dimensions without breaking cases where TIOCGWINSZ works.