Set size of a cygwin terminal window

Question

I have a small perl script, which is executed in a cygwin terminal and prints out a formatted table. On Default window size, cygwin will insert an line break if the text gets too long and thereby destroy the format of my table. Is there a way from my perl script to set the cygwin window to a bigger size to avoid that kind of problem?

Hassle

Answer 1

If you are using mintty as your terminal emulator (it has been the default terminal emulator for Cygwin for the past couple of years), you can use ANSI escape codes to manipulate the terminal.

You can test this by running the following snippet of Perl code to change the size of your terminal emulator window:

# If terminal supports ANSI escape sequences
$lines = 80;
$columns = 100;
print "\e[8;$lines;${columns}t";

Note: This doesn't work if run while in a screen window and I don't know why. According to the screen man page, this escape sequence should be supported.

Explanation

The syntax of ANSI escape sequences isn’t the easiest to read but here’s the documentation that provides the basis of the above sequence.

The \e prints an Escape character which begins the ANSI escape sequence. This is also known as the Control Sequence Introducer (CSI).

The specific sequence ending with t comes from this List of xterm control sequences

CSI Ps ; Ps ; Ps t
          Window manipulation (from dtterm, as well as extensions).
          These controls may be disabled using the allowWindowOps
          resource.  Valid values for the first (and any additional
          parameters) are:
…
Ps = 8  ;  height ;  width -> Resize the text area to given
          height and width in characters.  Omitted parameters reuse the
          current height or width.  Zero parameters use the display's
          height or width.

Bourges

I had expected this was impossible but it works in my Cygwin. Wow. – Lassiter

@DanielBöhmer Until I tried it, I wasn't sure which of xterm's control sequences were supported by mintty. In any case, I was fairly certain that the resizing wouldn't work with cmd.exe -- and it didn't. – Bourges

Answer 2

If you happen to be running this from a shortcut where you could add flags to the mintty command, you can set the size then. The benefit is that it looks smoother without the twitchy resize.

$ /cygdrive/c/tools/cygwin/bin/mintty.exe --help
Usage: mintty [OPTION]... [ PROGRAM [ARG]... | - ]

Start a new terminal session running the specified program or the user's shell.
If a dash is given instead of a program, invoke the shell as a login shell.

Options:
  -c, --config FILE     Load specified config file (cf. -C or -o ThemeFile)
  -e, --exec ...        Treat remaining arguments as the command to execute
  -h, --hold never|start|error|always  Keep window open after command finishes
  -p, --position X,Y    Open window at specified coordinates
  -p, --position center|left|right|top|bottom  Open window at special position
  -p, --position @N     Open window on monitor N
  -s, --size COLS,ROWS  Set screen size in characters (also COLSxROWS)
  -s, --size maxwidth|maxheight  Set max screen size in given dimension
  -t, --title TITLE     Set window title (default: the invoked command) (cf. -T)
  -w, --window normal|min|max|full|hide  Set initial window state
  -i, --icon FILE[,IX]  Load window icon from file, optionally with index
  -l, --log FILE|-      Log output to file or stdout
      --nobidi|--nortl  Disable bidi (right-to-left support)
  -o, --option OPT=VAL  Set/Override config file option with given value
  -B, --Border frame|void  Use thin/no window border
  -R, --Reportpos s|o   Report window position (short/long) after exit
      --nopin           Make this instance not pinnable to taskbar
  -D, --daemon          Start new instance with Windows shortcut key
  -H, --help            Display help and exit
  -V, --version         Print version information and exit
See manual page for further command line options and configuration.

Xylograph

Answer 3

You don't even need Perl, you can do the same in Bash:

echo -en "\e[8;35;100t";

Or why not a script:

#!/bin/bash
# minsize - A TTY re-size escape sequence for use with mintty Cygwin
# Usage: minsize <width> <height>
WIDTH=$1
HEIGHT=$2
echo -en "\e[8;${HEIGHT};${WIDTH}t";

Note, that on other *nixes there is ttysize available.

Pacifistic