bin/sh eval variable assignment

blasto333 · February 21, 2009, 2:21pm

Why can't I do this?
eval "TEST=5;echo $TEST;";

THIS WORKS!!
TEST=5;echo $TEST;

blasto333 · February 21, 2009, 2:26pm

I figured it out I have to escape \$

It also appears I have to escape backticks (`)

Why is this?

otheus · February 21, 2009, 7:07pm

eval tells the shell to take the parameters and interpret them as if they had just been typed on the command line. So take:

eval echo $TEST

the shell first interprolates the variables as normal, so eval sees:

eval echo 5

and so executes:

echo 5