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I've got a script I run like this:

node script.js

From within script.js, I would like to pass a variable back out to the shell for continued use.

I'll say it again in case you didn't get it the first time: basically, running the JS to come up with a variable, then I want to use that variable for a shell command. I tried looking this up and I didn't have much luck figuring it out. Simply doing console.log(foo=bar) doesn't work.

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The shell has to cooperate (well, usually -- you could force it to set the variable through gdb/ptrace, but that's very hacky and you could break the shell). You can output (console.log) the value and the shell can capture it:

variable=$(node script.js)

or you can output, e.g., evalable text that'll set the value and then eval it:

eval "$(node -e 'console.log("variable=42")')"
echo $variable
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Thanks, this worked well. In my situation, I combined it with IFS to get multiple variables out of the same JS file. IFS=,; set $(node script.js); var1=$1; var2=$2;

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