How do you append to an already existing string?

string bash shell string-concatenation
Mint picture Mint · Feb 12, 2010 · Viewed 245.7k times · Source

I want append to a string so that every time I loop over it will add say "test" to the string.

Like in PHP you would do:

$teststr = "test1\n"
$teststr .= "test2\n"
echo = "$teststr"

echos:

test1
test2

But I need to do this in a shell script

Answer

William Pursell picture William Pursell · Feb 12, 2010

In classic sh, you have to do something like:

s=test1
s="${s}test2"

(there are lots of variations on that theme, like s="$s""test2")

In bash, you can use +=:

s=test1
s+=test2

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