Davide Davide - 1 year ago 68
Bash Question

LINES and COLUMNS environmental variables lost in a script

Consider the following:

me@mine:~$ cat a.sh
echo "Lines: " $LINES
echo "Columns: " $COLUMNS
me@mine:~$ ./a.sh
me@mine:~$ echo "Lines: " $LINES
Lines: 52
me@mine:~$ echo "Columns: " $COLUMNS
Columns: 157

The variables
are shell variables, not environmental variables, and thus are not exported to the child process (but they are automatically updated when I resize the xterm window, even when logged in via ssh from a remote location). Is there a way in which I can let my script know the current terminal size?

I need this as a workaround do this problem: vi (as well as vim, less, and similar commands) messes up the screen every time I use it. Changing the terminal is not an option, and thus I'm looking for workarounds (scrolling down
lines surely is not the perfect solution, but at least is better than losing the previous screen)

Answer Source

You could get the lines and columns from tput


lines=$(tput lines)
columns=$(tput cols)

echo "Lines: " $lines
echo "Columns: " $columns
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