This is an extension of brainfuck to facilitate system programming. It includes a link editor, bold, and a dynamic loader, ld-bf.so. For now, it works exclusively on amd64 (aka x86_64) machines.

At program startup all cells will contain zero, except for the cell directly left of the starting cell which will contain its own address.

Accessing cells further left results in undefined behaviour.

All cells are 64 bits wide.

Command reference:

+   Increase value of current cell
-   Decrease value of current cell
>   Go right
<   Go left
[   Start loop
]   End loop
.   Write Character to stdout
,   Read Character from stdin
!   Do a syscall and store the result in the current cell.
    Before doing the call, the values of the next seven cells 
    beginning at the current are stored into %rax, %rdi, %rsi,
    %rdx, %r10, %r8 and %r9, in that order.
=   Copy cell contents. Can be chained. 
    (i.e. === -> copy value of current cell 3 cells to the right)
*   Interpret cell value as memory addres, and load

A: After compiling, we are left with assembler which is hard to read for many people. With this method the original source code will be preserved, which makes debugging easier.

A: By reusing library code, bugs and bad design choices made by the library implementer are propagated into user code. The only way to ensure bug-free and maintainable code is to write everything from scratch.

A: That's right. Fortunately, this package makes loading of libraries very easy. Just write a small C++-wrapper to call the desired function, implement a C++-compiler and linker to create an executable file, and call that binary using execv().

A: Before I can answer this, I need cover some prerequisites...hey, look at this cute kitten over there!

(Picture by Mel, CC BY-ND 2.0)

• Thread-local storage isn't properly implemented (yet?)

• bold should probably support a -static flag. Or any flag at all.

• I will be very impressed if someone manages to write a program that properly daemonizes and accepts incoming connections on a socket.