I'm using the following on Solaris:

  use Term::ANSIScreen qw/:screen/;
  my ($width, $height) = GetTerminalSize ();
[download]

# not portable -- linux only
sub getwinsize {
    my $winsize = "\0" x 8;
    my $TIOCGWINSZ = 0x40087468;
    if (ioctl(STDOUT, $TIOCGWINSZ, $winsize)) {
        ($rows, $cols, $xpixel, $ypixel) = unpack('S4', $winsize);
    } else {
        $cols = 80;
    }
}
[download]

You might do some research into termcap, which is the usual way of figuring out terminal capabilities and escape code sequences supported on a given Unix-style terminal. There are some CPAN modules which interface with the termcap facility.

Here are a couple of other snippets which may( or may not :-) ) work for you :

#!/usr/bin/perl
use Term::ReadKey;
($wchar, $hchar, $wpixels, $hpixels) = GetTerminalSize();

print "$wchar\t$hchar\t$wpixels\t$hpixels\n";
[download]

#!/usr/bin/perl

@x = qx(stty -a);
  @y = split(/;/, $x[0]);

print "screen size is $y[1] $y[2]\n";

########################################### 
#Also, you can specify 'size' to avoid parsing; 
($rows, $cols) = split ' ', qx"stty size </dev/tty 2>/dev/null";

print "screen size is $rows x $cols\n";
[download]

I was just thinking that the information should be available from stty, and was trying to figure out how to parse the output from stty, having forgotten about stty size.

Good on you, zentara++

use strict;
use Win32::Console;

my $CONSOLE = Win32::Console->new();

my ($width, $height) = $CONSOLE->Size();
# $CONSOLE->Size(80, 25); # force a console size

print "Console size is $width x $height\n";
[download]

Note that if the user resizes the window after the call to new(), the Size() method will not return the new size. If your application needs to handle resizing, it should create the Win32::Console object each time it needs to read the size.

I'd use the TIOCGWINSZ ioctl too.

A bit portable but slower is this:

($lines,$cols) = `stty size`=~/(\d+)\s+(\d+)/?($1,$2):(80,25);
[download]

Whichever you use, somewhat nicer would be to first check @ENV{qw{COLUMNS LINES}}, which are usually set to the screen size. Note that bash sets this variable automatically to correct values if the checkwinsize shopt is set.

You might also try to read the default values of the screen size from the termcap database and the TERM variable, if the other tries fail, before failing back to some hard-coded defaults. This might even help, as xterms are usually 24 high, while th elinux console is usually 25. (Update: oops, you wanted only the width, so this is stupid.) In today's world, however, when there are no more real terminals or consoles with fixes size, this loses from its significance, that's whi telnet and ssh tries to transfer the window size along with the TERMinal type.

Note that your application might also want to recalculate the screen size if it gets a SIGWINCH. The kernel or xterm or telnet etc automatically notifies the process with this signal when the console size changes.

There is something in %ENV, $ENV{'COLUMNS'}, if you export COLUMNS in your environment.