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.

In reply to Re: How to get the width of a console window? by ambrus
in thread How to get the width of a console window? by professa

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