Start work on tiocgwinsz.

src/Makefile

@@ -59,7 +59,7 @@ HACKERBASE-OBJS=hackerbase.o testing.o listing.o cal-month.o		\
 	 template-list-expander.o box-drawing.o export-web-static.o	\
 	 util-dir.o dokuwiki.o racket-kwargs.o duck.o util-bst.o	\
 	 util-bst-bdict.o util-bst-ldict.o util-bst-lset.o mailman2.o	\
-	 mailman-common.o mailman3.o mailman3-sql.o
+	 mailman-common.o mailman3.o mailman3-sql.o tiocgwinsz.o
 
 GENDOC-SOURCES=gendoc.scm duck-extract.import.scm			\
 	util-time.import.scm util-csv.import.scm util-git.import.scm	\
@@ -544,3 +544,8 @@ MAILMAN3-SQL-SOURCES=mailman3-sql.scm configuration.import.scm
 
 mailman3-sql.o: mailman3-sql.import.scm
 mailman3-sql.import.scm: $(MAILMAN3-SQL-SOURCES)
+
+TIOCGWINSZ-SOURCES=tiocgwinsz.scm
+
+tiocgwinsz.o: tiocgwinsz.import.scm
+tiocgwinsz.import.scm: $(TIOCGWINSZ-SOURCES)

src/tiocgwinsz.scm

@@ -0,0 +1,58 @@
+;;
+;; tiocgwinsz.scm
+;;
+;; Get size of current terminal.
+;;
+;; ISC License
+;;
+;; Copyright 2023 Brmlab, z.s.
+;; Dominik Pantůček <dominik.pantucek@trustica.cz>
+;;
+;; Permission to use, copy, modify, and/or distribute this software
+;; for any purpose with or without fee is hereby granted, provided
+;; that the above copyright notice and this permission notice appear
+;; in all copies.
+;; 
+;; THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+;; WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+;; WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+;; AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
+;; CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+;; OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+;; NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+;; CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+;;
+
+(declare (unit tiocgwinsz))
+
+(module
+ tiocgwinsz
+ (
+  tiocgwinsz
+  )
+
+ (import scheme
+	 (chicken foreign)
+	 (chicken bitwise))
+
+ (foreign-declare "#include <sys/ioctl.h>")
+
+ (define tiocgwinsz-ioctl
+   (foreign-lambda*
+    int ()
+    "
+struct winsize wss;
+if (ioctl(0, TIOCGWINSZ, &wss) == 0) {
+  C_return(wss.ws_row*65536+wss.ws_col);
+} else {
+  C_return(0);
+}
+"
+    ))
+
+ (define (tiocgwinsz)
+   (let ((res (tiocgwinsz-ioctl)))
+     (values (bitwise-and res #xffff)
+	     (arithmetic-shift res -16))))
+
+ )