- if (win) {
- NCURSES_CH_T old_bkgrnd;
- wgetbkgrnd(win, &old_bkgrnd);
+ /* avoid setting background-character to a null */
+ if (CharOf(new_bkgd) == 0) {
+ NCURSES_CH_T tmp_bkgd = blank;
+ SetAttr(tmp_bkgd, AttrOf(new_bkgd));
+ SetPair(tmp_bkgd, GetPair(new_bkgd));
+ new_bkgd = tmp_bkgd;
+ }
+
+ memset(&old_bkgd, 0, sizeof(old_bkgd));
+ (void) wgetbkgrnd(win, &old_bkgd);
+
+ if (!memcmp(&old_bkgd, &new_bkgd, sizeof(new_bkgd))) {
+ T(("...unchanged"));
+ returnCode(OK);
+ }
+
+ old_char = old_bkgd;
+ RemAttr(old_char, ~A_CHARTEXT);
+ old_attr = AttrOf(old_bkgd);
+ old_pair = GetPair(old_bkgd);
+
+ if (!(old_attr & A_COLOR)) {
+ old_pair = 0;
+ }
+ T(("... old background char %s, attr %s, pair %d",
+ _tracechar(CharOf(old_char)), _traceattr(old_attr), old_pair));