Bash – Iterating over multiple-line string stored in variable

bashread

I read that it is bad to write things like for line in $(command), the correct way seem to be instead:

command | while IFS= read -r line; do echo $line; done

This works great. But what if what I want to iterate on is the contents of a variable, not the direct result of a command?

For example, imagine that you create the following file quickfox:

The quick brown
foxjumps\ over -
the
lazy ,
dog.

I would like to be able to do something like this:

# This is just for the example,
# I could of course stream the contents to `read`
variable=$(cat quickfox);
while IFS= read -r line < $variable; do echo $line; done; # this is incorrect

Best Answer

In modern shells like bash and zsh, you have a very useful `<<<' redirector that accepts a string as an input. So you would do 

while IFS= read -r line ; do echo $line; done <<< "$variable"

Otherwise, you can always do

echo "$variable" | while IFS= read -r line ; do echo $line; done
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