How to concatenate stdin in to a pipe?

Question

I want to send the output of a pipe and stdin to a pipe in bash.

I.e:

gen_input | cat - | parse_input_and_stdin

would send the output of gen_input to parse_input_and_stdin and then leave stdin open for more interactive input.

Answer 1

Close.

{ gen_input ; cat ; } | parse_input_and_stdin

Answer 2

cat <(gen_input) - | parse_input_and_stdin