Tera Term

It can do with the combination of standard control sequences as follows.

• CUP: move cursor.
• CPR: get cursor position.
• DECSC: save cursor position.
• DECRC: restore cursor position.

cf. https://ttssh2.osdn.jp/manual/en/about/ctrlseq.html

here is the sample ruby script.

 #!/usr/bin/ruby
 #encoding: ascii-8bit
 
 require 'io/console'
 
 resp = ""
 
 STDIN.raw do |stdin|
   STDERR.print "\e7" # save cursor position
   STDERR.print "\e[999;999H" # move cursor to 999, 999
   STDERR.print "\e[6n" # query cursor position
   STDERR.print "\e8" # restore cursor position
 
   resp = ""
   while (c = stdin.getc)
     resp << c.chr
     break unless /[\[\x1b\x9c;0-9]/ =~ c
   end
 end
 
 if /(?:\x9c|\x1b\[)(\d+);(\d+)R/ =~ resp # check response of cursor position query
   rows = $1.to_i
   cols = $2.to_i
   puts "COLUMNS=#{cols}"
   puts "ROWS=#{rows}"
 else
   STDERR.puts "Invalid response"
 end

Another way, using the dtterm's window manipulation sequence.

Here is the sample bash script.

 #!/bin/bash
 
 die() {
         echo "$@"
         exit 1
 }
 
 printf "\e[18t"
 
 read -r -t 1 -n 3 resp
 [ $? -ne 0 ] && die "No response"
 
 CSI=$(printf "\x9b")
 ESC=$(printf "\e")
 
 case $resp in
 ${CSI}8\;)      : ;;
 ${ESC}\[8)
         read -r -t 1 -n 1 resp
         [ $? -ne 0 -o "$resp" != ";" ] && die "Invalid Response";;
 *)      die "Invalid Response";;
 esac
 
 state=0
 cols=0
 rows=0
 
 while [ $state -lt 3 ]; do
         read -r -t 1 -n 1 resp
         [ $? -ne 0 ] && die "Invalid Response"
 
         case $resp in
         [0-9])
                 if [ $state -eq 0 ]; then
                         rows=$((rows * 10 + resp))
                 elif [ $state -eq 1 ]; then
                         cols=$((cols * 10 + resp))
                 fi;;
         \;)     [ $state -lt 2 ] && state=$((++state));;
         t)      state=3;;
         *)      die "Invalid response";;
         esac
 done
 
 echo "COLUMNS=$cols"
 echo "ROWS=$rows"