curs_printw
Section: Library calls (3X)
Updated: 202-0-16
Index
Return to Main Contents
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(3X) 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 wid-character string to a
curses
window,
consider using
swprintf(3) and
waddwstr(3X) 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the latter is obsolete.
.IP * 4
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"TO BE WITHDRAWN",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.
.IP * 4
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vwscanw and the termcap interface) as withdrawn.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).
.IP * 4
ncurses
provides vwprintw,
but marks it as deprecated.
HISTORY
4BSD (1980)
introduced
wprintw
and its variants.
It implemented all as functions,
not macros;
this initial distribution of
curses
preceded the ANSI C standard of 1989,
prior to which a variadic macro facility was not widely available
in the language.
printw
went unused in Berkeley distributions until 4.1cBSD (1983),
which employed it in games.
4BSD's
wprintw
did not use
varargs.h,
which 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.
4BSD documented
printw
and
wprintw
tersely as "printf on
stdscr"
and "printf on
win",
respectively.
SVr3 summarized the functions in three lines,
asserting that they were analogous to printf(3)
and 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 added
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.
SEE ALSO
curses(3X),
curs_addstr(3X),
curs_scanw(3X),
printf(3),
vprintf(3)
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- RETURN VALUE
-
- NOTES
-
- PORTABILITY
-
- HISTORY
-
- SEE ALSO
-
|
|
- Running on 
-
:
