Why `\n` not working in Python

Question

I'm trying following example :

python -c "import sys; print sys.argv[1]" "test\ntest"

Output :

test\ntest

But I want following

test 
test

Update 1# As @devnull suggested can solve the problem if user itself pass the with $ but how about python should take care of this ?

I've tried :

python -c "import sys; print '$' + sys.argv[1]" 'test\ntest'

but output :

$test\ntest

Answer 1

As deed02392 mentioned, shell sends the characters literally, so python "escapes" the backslash internally. To see what I mean, try

python -c "import sys; print repr(sys.argv[1])" "test\ntest"
'test\\ntest'

To work around this, do:

python -c "import sys; print sys.argv[1].decode('string_escape')" "test\ntest"
test
test

Answer 2

Tell the shell to pass what you want to see:

python -c "import sys; print sys.argv[1]" $'test\ntest'

This would produce:

test
test

The $'string' syntax is referred to as ANSI-C Quoting.

---

Another way would be to tell the shell to interpret your original output:

python -c "import sys; print sys.argv[1]" 'test\ntest' | xargs -0 echo -en

This would also produce:

test
test