Flicker when stats are updated every second

[PartialVolume]

Flicker when stats are updated every second when nwipe is run not in a desktop terminal but in a full screen terminal such as when you select ALT-F2 or ALT-F3 and nwipe in that terminal etc.

Is a full screen update being done rather than a specific window update ?

Quote from the ncurses manual.

Causing Output to the Terminal
refresh() and wrefresh(win)
These functions must be called to actually get any output on the terminal, as other routines merely manipulate data structures. wrefresh() copies the named window to the physical terminal screen, taking into account what is already there in order to do optimizations. refresh() does a refresh of stdscr. Unless leaveok() has been enabled, the physical cursor of the terminal is left at the location of the window's cursor.
doupdate() and wnoutrefresh(win)
These two functions allow multiple updates with more efficiency than wrefresh. To use them, it is important to understand how curses works. In addition to all the window structures, curses keeps two data structures representing the terminal screen: a physical screen, describing what is actually on the screen, and a virtual screen, describing what the programmer wants to have on the screen. wrefresh works by first copying the named window to the virtual screen (wnoutrefresh()), and then calling the routine to update the screen (doupdate()). If the programmer wishes to output several windows at once, a series of calls to wrefresh will result in alternating calls to wnoutrefresh() and doupdate(), causing several bursts of output to the screen. By calling wnoutrefresh() for each window, it is then possible to call doupdate() once, resulting in only one burst of output, with fewer total characters transmitted (this also avoids a visually annoying flicker at each update).