You can't. But there are ways to get the number of columns other than environment variables. For example
COLUMNS=$(tput cols)
题
For the obvious reason I do not want to export COLUMNS
in my normal bash shell.
However for the purpose of one particular subshell, I need access to the value of COLUMNS of its parent. In other words, in a regular bash shell, I want to call a shell script that uses ls -Cw $COLUMNS
, with the value of $COLUMNS
from its parent.
Is there any way to access a parent's environment variables other than them being exported by the parent?
解决方案
You can't. But there are ways to get the number of columns other than environment variables. For example
COLUMNS=$(tput cols)