How to concatenate stdin and a string?

Question

How to I concatenate stdin to a string, like this?

echo \"input\" | COMMAND \"string\"

and get

inputstring

Answer 1

You can do it with sed:

seq 5 | sed '$a\6'
seq 5 | sed '$ s/.*/\0 6/'

In your example:

echo input | sed 's/.*/\0string/'