NAME

       notcurses_refresh - redraw an externally-damaged display

SYNOPSIS

       #include <notcurses/notcurses.h>

       int notcurses_refresh(const struct notcurses* nc, unsigned* restrict rows, unsigned* restrict cols);

DESCRIPTION

       notcurses_refresh clears the screen, homes the cursor, checks the current terminal geometry, and repaints
       the  most recently rendered frame.  It can be called concurrently with all other Notcurses functions save
       notcurses_render.  notcurses_refresh ought be called when the screen is  externally  damaged  (as  occurs
       when  another  program  writes  to the terminal, or if your program writes to the terminal using standard
       I/O).  It is necessary to use notcurses_refresh in such a case (as opposed  to  simply  calling  notcurs‐
       es_render),  since  notcurses_render  optimizes  its  output  by  only  writing internally-damaged cells.
       Notcurses has no way of knowing about external corruption; by tradition, Ctrl+L is bound to notcurses_re‐
       fresh, and the user is responsible for requesting a hard redraw.

       A secondary use of this function is when the program is blocking on input (and perhaps not ready to  ren‐
       der), and receives an NCKEY_RESIZE event (see notcurses_input).  In this case, notcurses_refresh will ac‐
       quire  the  new screen parameters, and repaint what it can.  If you're prepared to call notcurses_render,
       it's better to do that in this case, and thus avoid unnecessary screen redrawing.

       If rows and/or cols is not NULL, they receive the new geometry.

NOTES

       If your program is in a render loop (i.e.  rendering as quickly as possible, or at least at  the  refresh
       rate),  there's not much point in erecting the machinery to trigger notcurses_refresh based off NCKEY_RE‐
       SIZE.  The latter is generated based upon receipt of the SIGWINCH signal,  which  is  fundamentally  racy
       with  regards  to the rest of the program.  If your program truly relies on timely invocation of notcurs‐
       es_refresh, it's a broken program.  If you don't rely on it in a causal fashion, then just wait  for  the
       upcoming render.

       Highest  performance  in a rendering loop would actually call for disabling Notcurses's SIGWINCH handling
       in the call to notcurses_init, so that no time is spent handling a signal you're not going to use.

       Each time notcurses_refresh is successfully executed, the refreshes stat is incremented by 1.

RETURN VALUES

       Returns 0 on success, and -1 on failure.  The causes for failure include system error, programming error,
       closing of output, or allocation failure.  None of these are particularly good things, and the most  rea‐
       sonable response to a notcurses_refresh failure is either to ignore it, or to weep and exit.

SEE ALSO

       notcurses_init(3), notcurses_input(3), notcurses_render(3), notcurses_stats(3), termios(3), signal(7)

AUTHORS

       nick black <nickblack@linux.com>.

                                                     v3.0.7                                 notcurses_refresh(3)