1curs_printw(3X) curs_printw(3X)
2
6 printw, wprintw, mvprintw, mvwprintw, vwprintw, vw_printw - print
7 formatted output in curses windows
8
10 #include <curses.h>
11 int printw(const char *fmt, ...);
13 int wprintw(WINDOW *win, const char *fmt, ...);
14 int mvprintw(int y, int x, const char *fmt, ...);
15 int mvwprintw(WINDOW *win, int y, int x, const char *fmt, ...);
16 int vw_printw(WINDOW *win, const char *fmt, va_list varglist);
17 /* obsolete */
19 int vwprintw(WINDOW *win, const char *fmt, va_list varglist);
20
22 The printw, wprintw, mvprintw and mvwprintw routines are analogous to
23 printf [see printf(3)]. In effect, the string that would be output by
24 printf is output instead as though waddstr were used on the given win‐
25 dow.
26 The vwprintw and vw_printw routines are analogous to vprintf [see
28 printf(3)] and perform a wprintw using a variable argument list. The
29 third argument is a va_list, a pointer to a list of arguments, as de‐
30 fined in <stdarg.h>.
31
33 Routines that return an integer return ERR upon failure and OK (SVr4
34 only specifies "an integer value other than ERR") upon successful com‐
35 pletion.
36 X/Open defines no error conditions. In this implementation, an error
38 may be returned if it cannot allocate enough memory for the buffer used
39 to format the results. It will return an error if the window pointer
40 is null.
41 Functions with a “mv” prefix first perform a cursor movement using
43 wmove, and return an error if the position is outside the window, or if
44 the window pointer is null.
45
47 While printw was implemented in 4BSD, it was unused until 4.2BSD (which
48 used it in games). That early version of curses was before the ANSI C
49 standard. It did not use <varargs.h>, though that was available. In
50 1991 (a couple of years after SVr4 was generally available, and after
51 the C standard was published), other developers updated the library,
52 using <stdarg.h> internally in 4.4BSD curses. Even with this improve‐
53 ment, BSD curses did not use function prototypes (or even declare func‐
54 tions) in the <curses.h> header until 1992.
55 SVr2 documented printw, wprintw tersely as “printf on stdscr” and
57 tersely as “printf on win”, respectively.
58 SVr3 added mvprintw, and mvwprintw, with a three-line summary saying
60 that they were analogous to printf(3), explaining that the string which
61 would be output from printf(3) would instead be output using waddstr on
62 the given window. SVr3 also added vwprintw, saying that the third pa‐
63 rameter is a va_list, defined in <varargs.h>, and referring the reader
64 to the manual pages for varargs and vprintf for detailed descriptions.
65 SVr4 added no new variations of printw, but provided for using
67 <varargs.h> or <stdarg.h> to define the va_list type.
68 X/Open Curses added vw_printw to replace vwprintw, stating that its
70 va_list definition requires <stdarg.h>.
71
73 In this implementation, vw_printw and vwprintw are equivalent, to sup‐
74 port legacy applications. However, the latter (vwprintw) is obsolete:
75 • The XSI Curses standard, Issue 4 described these functions. The
77 function vwprintw is marked TO BE WITHDRAWN, and is to be replaced
78 by a function vw_printw using the <stdarg.h> interface.
79 • The Single Unix Specification, Version 2 states that vw_printw is
81 preferred to vwprintw since the latter requires including
82 <varargs.h>, which cannot be used in the same file as <stdarg.h>.
83 This implementation uses <stdarg.h> for both, because that header
84 is included in <curses.h>.
85 • X/Open Curses, Issue 5 (December 2007) marked vwprintw (along with
87 vwscanw and the termcap interface) as withdrawn.
88
90 curses(3X), curs_addstr(3X), curs_scanw(3X), curs_termcap(3X),
91 printf(3), vprintf(3).
92 curs_printw(3X)