24 июн. 2020 г. · Then, a variable can be set to an empty string or it can be unset. Set the variable if it isn't already set, or if it's set to NULL ( \0 ) or ...

13 дек. 2018 г. · To declare a variable in Bash, say in a Bash script-file (that doesn't include Bash function), I do for example x=y and when I finish using it ...

5 мар. 2020 г. · I have the following script and I try to create an empty text file. I tried touch and I tried echo -n > - they both fail.

22 апр. 2016 г. · You make a variable assignment an environment variable by using export, such as export foo=bar. This is the bash syntax, other shells may use env or some other ...

24 окт. 2014 г. · Use a Bash Substitution Expansion If you're using Bash, you can use a substitution expansion. For example: $ echo "${VAR// /}" This displays ...

28 апр. 2014 г. · The variables are expanded before the variable assignment takes place. For the obvious reason that var=x would work the other way, too, but var ...

6 июн. 2015 г. · The exit code is always assigned to $?, so you can do function0() { (exit 1) echo "$?" } to get the effect you're looking for.

3 апр. 2014 г. · This technique allows for a variable to be assigned a value if another variable is either empty or is undefined.

27 сент. 2020 г. · I would like to ensure all of the variables are set (not left blank) and ensure they are entered correctly before the script can continue and automatically do ...

6 сент. 2018 г. · To get both variables assigned from a single setting of the variable, you'll need to get both from the subshell.