c - Input string with non printable chars

Question

In a Linux console when a C program asks for a string (i.e. username) how can I insert non-printable chars?
I search something better then
printf 'x48x83xc4x50x48xbfx3d...etc' | ./myProgram.bin
or
./myProgram.bin < dataFile
I prefer to type chars when needed but I don't know how to write non-printable ones.
Thank you

Answer 1

It worked using xclip (printf 'x48x83...' | xclip) to copy the string to clipboard.
Then, when the program asks for the string, I used SHIFT+CTRL+V to paste the string.
It generally works, except for certain characters (x08, ...) that the input function (gets, ...) can ignore or use as control character.