NAME

       Beef - Flexible Brainfuck interpreter

SYNOPSIS

       beef [OPTION]... FILE

DESCRIPTION

       Beef is a flexible interpreter for the Brainfuck programming language.

       It can be configured using the options described below, making it possible to run Brainfuck programs that
       make assumptions about the behavior of the interpreter.

       Beef  sets  no  arbitrary  limit to the size of the memory tape used by the program, and allocates memory
       cells as they are needed.

OPTIONS

       -s, --store=WHAT
              Choose the value to store in the tape when the end of input is reached.  WHAT defaults  to  `zero'
              (store  a  zero);  other  possible values are `eof' (store -1, the value usually assigned to the C
              constant EOF) or `same' (leave the value untouched)

       -d, --enable-debugging
              Enable debugging support.  By default, debugging instructions are not executed

       -o, --output-file=FILE
              Write program's output to FILE

       -i, --input-file=FILE
              Read program's input from FILE

       FILE can be local path or any URI supported by GIO.  If FILE is `-' standard input  or  standard  output,
       depending on the context, will be used.

BRAINFUCK LANGUAGE

       Brainfuck  programs work on a memory tape which contains a virtually unlimited number of cells; each cell
       can store a value, which can be seen either as a character or as an integer number (its  ASCII  encoding)
       depending  on the context.  There is a cursor pointing to one of the cells, which is considered to be the
       current one; the cursor can be moved around at will.

       A Brainfuck source file is made of a number of Brainfuck instructions; any symbol which  is  not  an  in‐
       struction is considered a comment and is ignored.  There are exceptions to this rule, see below.

       The Brainfuck instructions are:

       +      Increase the value in the current cell by one

       -      Decrease the value in the current cell by one

       >      Move the cursor one cell to the right

       <      Move the cursor one cell to the left

       [      Start  a  loop.   The  instructions contained in the loop are executed as long as the value of the
              current cell is not zero

       ]      End a loop started by a [ instruction

       ,      Read a character from the input and store it in che current cell

       .      Write the value of the current cell to the output

       #      Dump the content of the memory tape for debugging purposes.  This instruction  is  ignored  unless
              the --enable-debugging option is present

       If the first line of the source file starts with the magic sequence #! it is ignored.  This allows you to
       execute a Brainfuck program without calling Beef explicitly, like you would do for eg.  a Python program.

       The symbol ! has a special meaning to Beef: it marks the end of a program's code and the beginning of its
       input.  If this symbol is present in the source file, runtime input will be ignored.

EXAMPLES

       The classic Hello World program could be written in Brainfuck as

                  ++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.++++++
                  +..+++.>++.<<+++++++++++++++.>.+++.------.--------.>+.>.

       The following Brainfuck program can be used to replace the cat(1) utility:

                  #!/usr/bin/beef
                  ,[.,]

       That's of course assuming you don't need any of cat(1)'s fancy commandline options, you have a shell with
       working I/O redirection and a sense of humor.

AUTHORS

       Andrea Bolognani <eof@kiyuko.org>.

Beef 1.0.2                                        January 2017                                           BEEF(1)