ncurses 6.2 - patch 20200314

[ncurses.git] / man / curs_scanw.3x

diff --git a/man/curs_scanw.3x b/man/curs_scanw.3x
index 9407ae6489d8fe4b0976409cf9d07722d61f3266..870b4b4cb72d5eede887c4f8a1932aef8aa0b936 100644 (file)
--- a/man/curs_scanw.3x
+++ b/man/curs_scanw.3x
@@ -27,7 +27,7 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
-.\" $Id: curs_scanw.3x,v 1.26 2020/02/02 23:34:34 tom Exp $
+.\" $Id: curs_scanw.3x,v 1.27 2020/03/15 00:14:30 tom Exp $
 .TH curs_scanw 3X ""
 .ie \n(.g .ds `` \(lq
 .el       .ds `` ``
@@ -83,6 +83,44 @@ which were mapped in the call.
 Functions with a \*(``mv\*('' prefix first perform a cursor movement using
 \fBwmove\fP, and return an error if the position is outside the window,
 or if the window pointer is null.
+.SH HISTORY
+While \fBscanw\fP was implemented in 4BSD,
+none of the BSD releases used it until 4.4BSD (in a game).
+That early version of curses was before the ANSI C standard.
+It did not use <varargs.h>, though that was available.
+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 (or even declare
+functions) in the <curses.h> header until 1992.
+.PP
+SVr2 documented
+\fBscanw\fP,
+\fBwscanw\fP
+tersely as \*(``scanf through \fIstdscr\fP\*('' and
+tersely as \*(``scanf through \fIwin\fP\*('', respectively.
+.PP
+SVr3 added
+\fBmvscanw\fP, and
+\fBmvwscanw\fP, with a three-line summary saying that they were analogous
+to \fBscanf\fP(3),
+explaining that the string which would be output from \fBscanf\fP(3) would
+instead be output using \fBwaddstr\fP on the given window.
+SVr3 also added \fBvwscanw\fP, saying that the third parameter
+is a \fBva_list\fP, defined in <varargs.h>,
+and referring the reader to the manual pages for \fIvarargs\fP and
+\fIvprintf\fP for detailed descriptions.
+(Because the SVr3 documentation does not mention \fIvscanf\fP,
+that reference to \fIvprintf\fP may not be an error).
+.PP
+SVr4 added no new variations of \fBscanw\fP,
+but provided for using <varargs.h> or <stdarg.h> to define the \fBva_list\fP
+type.
+.PP
+X/Open Curses added \fBvw_scanw\fP to replace \fBvwscanw\fP,
+stating that its \fBva_list\fP definition requires <stdarg.h>.
 .SH PORTABILITY
 In this implementation, \fBvw_scanw\fP and \fBvwscanw\fP are equivalent,
 to support legacy applications.