X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=doc%2Fhtml%2Fman%2Fcurs_pad.3x.html;h=b065000bfd5d5a6619c12a506c4052008eb11a85;hp=fa9c5a45dcaffb7fb536a3e82688d41bb5ed70c3;hb=a90dd7b66fa711acd24d8181ea20e4f57d4b36cd;hpb=ed646e3f683083e787c6ba773364401dc9fa9d40;ds=sidebyside
diff --git a/doc/html/man/curs_pad.3x.html b/doc/html/man/curs_pad.3x.html
index fa9c5a45..b065000b 100644
--- a/doc/html/man/curs_pad.3x.html
+++ b/doc/html/man/curs_pad.3x.html
@@ -1,6 +1,7 @@
-
+
curs_pad 3x
-
+
@@ -74,8 +75,10 @@
screen. Pads can be used when a large window is needed, and only a
part of the window will be on the screen at one time. Automatic re-
freshes of pads (e.g., from scrolling or echoing of input) do not oc-
- cur. It is not legal to call wrefresh with a pad as an argument; the
- routines prefresh or pnoutrefresh should be called instead. Note that
+ cur.
+
+ It is not legal to call wrefresh with a pad as an argument; the rou-
+ tines prefresh or pnoutrefresh should be called instead. Note that
these routines require additional parameters to specify the part of the
pad to be displayed and the location on the screen to be used for the
display.
@@ -95,15 +98,19 @@
The prefresh and pnoutrefresh routines are analogous to wrefresh and
wnoutrefresh except that they relate to pads instead of windows. The
additional parameters are needed to indicate what part of the pad and
- screen are involved. The pminrow and pmincol parameters specify the
- upper left-hand corner of the rectangle to be displayed in the pad.
- The sminrow, smincol, smaxrow, and smaxcol parameters specify the edges
- of the rectangle to be displayed on the screen. The lower right-hand
- corner of the rectangle to be displayed in the pad is calculated from
- the screen coordinates, since the rectangles must be the same size.
- Both rectangles must be entirely contained within their respective
- structures. Negative values of pminrow, pmincol, sminrow, or smincol
- are treated as if they were zero.
+ screen are involved.
+
+ o The pminrow and pmincol parameters specify the upper left-hand cor-
+ ner of the rectangle to be displayed in the pad.
+
+ o The sminrow, smincol, smaxrow, and smaxcol parameters specify the
+ edges of the rectangle to be displayed on the screen.
+
+ The lower right-hand corner of the rectangle to be displayed in the pad
+ is calculated from the screen coordinates, since the rectangles must be
+ the same size. Both rectangles must be entirely contained within their
+ respective structures. Negative values of pminrow, pmincol, sminrow,
+ or smincol are treated as if they were zero.
- The XSI Curses standard, Issue 4 describes these functions.
+ BSD curses has no pad feature.
+
+ SVr2 curses (1986) provided the newpad and related functions, document-
+ ing them in a single line each. SVr3 (1987) provided more extensive
+ documentation.
+
+ The documentation does not explain the term pad. However, the Apollo
+ Aegis workstation operating system supported a graphical pad feature:
+
+ o These graphical pads could be much larger than the computer's dis-
+ play.
+
+ o The read-only output from a command could be scrolled back to in-
+ spect, and select text from the pad.
+
+ The two uses may be related.
+
+ The XSI Curses standard, Issue 4 describes these functions, without
+ significant change from the SVr3 documentation. It describes no error
+ conditions. The behavior of subpad if the parent window is not a pad
+ is undocumented, and is not checked by the vendor Unix implementations:
+
+ o SVr4 curses sets a flag in the WINDOW structure in newpad which
+ tells if the window is a pad.
+
+ However, it uses this information only in waddch (to decide if it
+ should call wrefresh) and wscrl (to avoid scrolling a pad), and
+ does not check in wrefresh to ensure that the pad is refreshed
+ properly.
+
+ o Solaris X/Open Curses checks if a window is a pad in wnoutrefresh,
+ returning ERR in that case.
+
+ However, it only sets the flag for subwindows if the parent window
+ is a pad. Its newpad function does not set this information. Con-
+ sequently, the check will never fail.
+
+ It makes no comparable check in pnoutrefresh, though interestingly
+ enough, a comment in the source code states that the lack of a
+ check was an MKS extension.
+
+ o NetBSD 7 curses sets a flag in the WINDOW structure for newpad and
+ subpad, using this to help with the distinction between wnoutre-
+ fresh and pnoutrefresh.
+
+ It does not check for the case where a subwindow is created in a
+ pad using subwin or derwin.
+
+ The dupwin function returns a regular window when duplicating a
+ pad. Likewise, getwin always returns a window, even if the saved
+ data was from a pad.
+
+ This implementation
+
+ o sets a flag in the WINDOW structure for newpad and subpad,
+
+ o allows a subwin or derwin call to succeed having a pad parent by
+ forcing the subwindow to be a pad,
+
+ o checks in both wnoutrefresh and pnoutrefresh to ensure that pads
+ and windows are handled distinctly, and
+
+ o ensures that dupwin and getwin treat pads versus windows consis-
+ tently.