This question might be a bit pointless, but I thought it was interesting and I don't know how to find an answer to it otherwise.
I wrote a brainfuck interpreter that takes programs (or file paths) as arguments from the command line; i.e.
Your problem are not square backets. You problem are
>. They are intended to handle stream redirection,
< xxx means get input from xxx,
> xxx means send output to xxx
You can enclose the text in double quotes or can escape the "problematic" characters preceding them with a caret
brainfuck ">++++++++[<++++++++>-]<." brainfuck ^>++++++++[^<++++++++^>-]^<.