Ubuntu Manpage: printw, wprintw, mvprintw, mvwprintw, vwprintw, vw_printw

NAME

       printw,  wprintw,  mvprintw,  mvwprintw, vwprintw, vw_printw - write formatted output to a
       curses window

SYNOPSIS

       #include <curses.h>

       int printw(const char *fmt, ...);
       int wprintw(WINDOW *win, const char *fmt, ...);
       int mvprintw(int y, int x, const char *fmt, ...);
       int mvwprintw(WINDOW *win, int y, int x, const char *fmt, ...);

       int vw_printw(WINDOW *win, const char *fmt, va_list varglist);

       /* obsolete */
       int vwprintw(WINDOW *win, const char *fmt, va_list varglist);

DESCRIPTION

       printw, wprintw, mvprintw, and mvwprintw are  analogous  to  printf(3).   In  effect,  the
       string  that  would  be  output by printf(3) is instead output as though waddstr(3NCURSES)
       were used with win (or stdscr) as its first argument.

       vwprintw and vw_printw are analogous to vprintf(3), and perform a wprintw using a variable
       argument  list.   The  third  argument  is a va_list, a pointer to a list of arguments, as
       defined in stdarg.h.

RETURN VALUE

       These functions return ERR upon failure and OK upon success.

       In ncurses, failure occurs if the library cannot allocate enough  memory  for  the  buffer
       into which the output is formatted, or if the window pointer win is null.

       Functions prefixed with “mv” first perform cursor movement and fail if the position (y, x)
       is outside the window boundaries.

NOTES

       No wide character counterpart functions are defined by the  “wide”  ncurses  configuration
       nor  by  any  standard.   To  format and write a wide-character string to a curses window,
       consider using swprintf(3) and waddwstr(3NCURSES) or similar.

PORTABILITY

       X/Open Curses, Issue 4 describes these functions.  It specifies no  error  conditions  for
       them.

       ncurses  defines  vw_printw  and  vwprintw  identically  to  support  legacy applications.
       However, the latter is obsolete.

       •   X/Open Curses, Issue 4 Version 2 (1996), marked vwprintw as  requiring  varargs.h  and
           “TO BE WITHDRAWN”, and specified vw_printw using the stdarg.h interface.

       •   X/Open  Curses,  Issue  5, Draft 2 (December 2007) marked vwprintw (along with vwscanw
           and the termcap interface) as withdrawn.  After incorporating  review  comments,  this
           became X/Open Curses, Issue 7 (2009).

       •   ncurses provides vwprintw, but marks it as deprecated.

HISTORY

While printw was implemented in 4BSD (November 1980), it was unused until 4.2BSD (August
1983), which employed it for games. That early version of curses preceded the ANSI C
standard of 1989. It did not use varargs.h, though that had been available since Seventh
Edition Unix (1979). In 1991 (a couple of years after SVr4 was generally available, and
after the C standard was published), other developers updated the library, using stdarg.h
internally in 4.4BSD curses. Even with this improvement, BSD curses did not use function
prototypes (nor even declare functions) in curses.h until 1992.

SVr2 (1984) documented printw and wprintw tersely as “printf on stdscr” and “printf on
win”, respectively.

SVr3 (1987) added mvprintw and mvwprintw, with a three-line summary asserting that they
were analogous to printf(3), explaining that the string that printf(3) would write to the
standard output stream would instead be output using waddstr to the given window. SVr3
also implemented vwprintw, describing its third parameter as a va_list, defined in
varargs.h, and referred the reader to the manual pages for varargs and vprintf for
detailed descriptions.

SVr4 (1989) introduced no new variations of printw, but provided for using either
varargs.h or stdarg.h to define the va_list type.

X/Open Curses, Issue 4 (1995), defined vw_printw to replace vwprintw, stating that its
va_list type is defined in stdarg.h.