Apple II FTN - Binary II File

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Apple II
File Type Notes
                                                  Developer Technical Support

File Type:         $E0 (224)
Auxiliary Type:    $8000

Full Name:     Binary II File
Short Name:    Binary II File

Written by:    Matt Deatherage                                      July 1989

Files of this type and auxiliary type contain other files with their 
attributes encoded in Binary II format.

Binary II is a widely used and accepted standard for keeping file attributes 
with files as they are transferred, usually by modem or other form of 
telecommunication.  Files that are known Binary II files should be written to 
disk with file type $E0 and auxiliary type $8000 as a clear indication to 
other programs that the file contains files with Binary II specifications.

Binary II was developed by Gary B. Little, author of the Point-To-Point 
communication's product and author of several Apple II reference books.  He is 
also Apple's Product Manager for third-party Development Tools and Languages.  
Gary welcomes your comments and suggestions on the Binary II standard at the 
following address:

                Gary B. Little
                3304 Plateau Drive
                Belmont, CA  94002

                AppleLink:                      LITTLE
                AppleLink--Personal Edition:    GaryLittle
                CompuServe:                     70135,1007
                GEnie:                          GARY.LITTLE

Why Binary II?

Transferring Apple II files in binary form to commercial information services 
and bulletin boards (referred to in this Note as "hosts") can be, to put it 
mildly, a frustrating exercise.  Although most hosts are able to receive a 
file's data in binary form (using protocols such as XMODEM), they don't 
receive the file's all-important attribute bytes.  All the common Apple II 
file system, notably the ProDOS file system, store the attributes inside the 
disk directory, not inside the file itself.

The ProDOS attributes are the access code, file type code, auxiliary type 
code, storage type code, date of creation and last modification, time of 
creation and last modification, the file size, and the name of the file 
itself.  Under GS/OS, the same parameters exist for other file systems as well 
as file system-specific information and two-forked file information.  It is 
usually not possible to use a ProDOS file's data without knowing the file's 
attributes (particularly the file type, auxiliary type, and size).  Therefore, 
ProDOS files uploaded in binary format to a host are useless to those who 
download them.  The same is true for DOS 3.3 and Pascal files.

Many Apple II communication programs use special protocols for transferring 
file attributes during a binary file transfer, but none of these protocols 
have been implemented by hosts.  These programs are only useful for exchanging 
files with another Apple II running the same program.

Without a standard like Binary II, the only acceptable way to transfer an 
Apple II file to a host is to convert it into ASCII text before sending it.  
Such a text file would contain a listing of an AppleSoft program, or a series 
of Apple II monitor commands (e.g., 300:A4 32).  Someone downloading a file 
can convert it to binary form using the AppleSoft EXEC command.

The main disadvantage of this technique is that the text version of the file 
is over three times the size of the original binary file, making it expensive 
(in terms of time and money) to upload and download.  It is also awkward, and 
sometimes impossible, to perform the binary-to-text or text-to-binary 

The solution to the problem is to upload an encoded binary file which contains 
not just the file's data, but the file's attributes as well.  Someone 
downloading such a file can then use a conversion program to strip the 
attributes from the file and create a file with the required attributes.

This Note describes such a format:  Binary II.  The description of the format 
is detailed for the purpose of allowing software developers to implement it in 
Apple II communication programs.

What Binary II is Not

Binary II is not an archival or compression standard.  It is designed to be a 
simple method to keep the attributes normally in a disk file's directory entry 
with the file as it is transferred.  Although multiple files may be placed 
together with Binary II, this is a matter of convenience for telecommunication 

A true archival standard must be designed as such, with the capability to 
manipulate files within the archive as well as linking them together 
(compressed or uncompressed) for transfer.  NuFX (documented in Apple II File 
Type Note for File Type $E0, Auxiliary Type $8002) is a good example of a 
robust, full-featured Apple II archival standard.

Binary II is primarily designed to be added to and subtracted from files "on-
the-fly" by telecommunication programs.  Binary II files should only be found 
on disks when they are transferred by a telecommunication program that does 
not have Binary II capabilities, in which case a separate utility (such as 
Binary Library Utility by Floyd Zink, Jr.) must be used to extract the files.  
Telecommunication programs should be able to transfer files without Binary II 
processing, however, they should support Binary II processing as a default.

The Binary II File Format

The Binary II form of a standard file consists of a 128-byte file information 
header followed by the file's data.  The data portion of the file is padded 
with nulls ($00 bytes), if necessary, to ensure the data length is an even 
multiple of 128 bytes.

The file information header contains four ID bytes, the attributes of the file 
(in ProDOS 8 form), and some control information.

The structure of the header is as follows:

+000    ID Bytes   3 Bytes  These three bytes are always $0A $47 $4C 
                            for identification purposes, so programs 
                            may recognize Binary II files as they are 
+003    Access Code Byte    ProDOS 8 access byte.
+004    File Type  Byte     ProDOS 8 file type.
+005    Aux Type   Word     ProDOS 8 auxiliary type.
+007    Storage Type Byte   ProDOS 8 storage type value.
+008    File Size   Word    The size of the file in 512-byte blocks.
+010    Mod. Date   2 Bytes Date of modification, in ProDOS 8 
                            compressed format.
+012    Mod. Time   2 Bytes Time of modification, in ProDOS 8 
                            compressed format.
+014    Create Date 2 Bytes Date of creation, in ProDOS 8 
                            compressed format.
+016    Create Time 2 Bytes Time of creation, in ProDOS 8 
                            compressed format.
+018    ID Byte     Byte    A fourth ID byte.  This must always be 
+019    Reserved    Byte    Reserved, must be set to zero.
+020    EOF         3 Bytes The end-of-file value for the file (low 
                            byte first).
+023    File Name   String  Pascal string containing the ASCII 
                            filename or partial pathname of this file 
                            in ProDOS 8 format.  The string cannot be 
                            longer than 64 characters.

If the File Name String is a filename and not a partial pathname, then the 
following optional parameter may be supplied:

+039    Native Name String  Pascal string containing the 
                            ASCII value of the native filename.  This 
                            string may not be longer than 48 
                            characters, and will not be present if the 
                            length byte of File Name (+023) is larger 
                            than 15 ($0F).  If this field is 
                            specified, the File Name field must 
                            contain a filename, not a partial 

+088    Reserved   21 Bytes Reserved.  These bytes must be set to zero 
                            for future compatibility.

+109    GAux Type  Word     The high word of the file's GS/OS 
                            auxiliary type.
+111    GAccess    Byte     The high byte of the file's GS/OS access 
+112    GFile Type Byte     The high byte of the file's GS/OS 
                            file type.
+113    GStorage   Byte     The high byte of the file's GS/OS storage 
+114    GFile Size Word     The high word of the GS/OS file's 
                            size in 512-byte blocks.
+116    GEOF       Byte     The high byte of the file's GS/OS EOF 
+117    Disk Space Long     The number of 512-byte disk blocks 
                            the files inside the Binary II file will 
                            occupy after they've been removed from the 
                            Binary II file.  (The format of a Binary 
                            II file containing multiple files is 
                            described later in this Note.)  If the 
                            number is zero, the creator of the Binary 
                            II file didn't bother to calculate the 
                            space needed.  This value must be placed 
                            in the file information header for the 
                            first file inside the Binary II file; it 
                            can be set to zero in subsequent headers.  
                            A downloading program can inspect Disk 
                            Space and abort the transfer immediately 
                            if there isn't enough free space on the 
+121    OS Type    Byte     This value indicates the native operating 
                            system of the file:
                            $00    ProDOS or SOS
                            $01    DOS 3.3
                            $02    Reserved
                            $03     DOS 3.2 or DOS 3.1
                            $04    Apple II Pascal
                            $05    Macintosh MFS
                            $06    Macintosh HFS
                            $07    Lisa Filing System
                            $08    Apple CP/M
                            $09    Reserved (returned by the GS/OS 
                                   Character FST)
                            $0A    MS-DOS
                            $0B    High Sierra (CD-ROM)
                            $0C    ISO 9660 (CD-ROM)
                            $0D    AppleShare
                            Note this list is slightly different (in 
                            the first three entries) from the standard 
                            GS/OS file system ID list.  A GS/OS 
                            communication program should not place a 
                            zero in this field unless the file's 
                            native file system truly is ProDOS.  The 
                            file's native file system is returned in 
                            the file_sys_id parameter from the 
                            GetDirEntry call.
+122    Native File Type
                   Word     This has meaning only if OS Type is non-
                            zero.  If so, it is set to the actual file 
                            type code assigned to the file by it's 
                            native operating system.  (Some operating 
                            systems, such as MS-DOS and CP/M, do not 
                            use file type codes, however.)  Contrast 
                            this with the File Type at +004, which is 
                            the closest equivalent ProDOS file type.  
                            The Native File Type is needed to 
                            distinguish files which have the same 
                            ProDOS file type, but which may have 
                            different file types in their native 
                            operating system.  Note that if the file 
                            type code is only one byte long (the usual 
                            case), the high-order byte of Native File 
                            Type is set to zero.
+124    Phantom File Flag
                   Byte     This byte indicates whether a receiver of 
                            the Binary II file should save the file 
                            which follows (flag is zero) or ignore it 
                            (flag is non-zero).  It is anticipated 
                            that some communication programs will use 
                            phantom files to pass non-essential 
                            explanatory notes or encoded information 
                            which would be understood only by a 
                            receiver using the same communication 
                            program.  Such programs must not rely on 
                            receiving a phantom file, however, since 
                            this would mean they couldn't handle 
                            Binary II files created by other 
                            communication programs.  Phantom Files may 
                            also be used to pass extended file 
                            attributes when available.

                            The first two bytes in a phantom file must 
                            contain an ID code unique to the 
                            communication program, or a universal 
                            identifier concerning the contents of the 
                            phantom file.  Developers must obtain ID 
                            codes from Gary Little to ensure 
                            uniqueness (see the beginning of this Note 
                            for his address).  Here is a current list 
                            of approved ID codes for phantom files 
                            used by Apple II communication programs:
                            $00 $00    ASCII text terminated with a 
                                       zero byte.
                            $00 $01    Point-to-Point
                            $00 $02    Tele-Master Communications 
                            $00 $03    ProTERM
                            $00 $04    Modem MGR
                            $00 $05    CommWorks
                            $00 $06    MouseTalk
                            $01 $00    Option_list data (see later in 
                                       this Note).
                            The ID bytes are the first two bytes of 
                            the phantom file.
+125    Data Flags          Bit 7:    1 = file is compressed
                  Flag Byte Bit 6:    1 = file is encrypted
                            Bits 5-1: Reserved
                            Bit 0:    1 = file is sparse
                            A Binary II downloading program can 
                            examine this byte and warn the user that 
                            the file must be expanded, decrypted or 
                            unpacked.  The person uploading a Binary 
                            II file may use any convenient method for 
                            compressing, encrypting, or packing the 
                            file but is responsible for providing 
                            instructions on how to restore the file to 
                            its original state.
+126    Version    Byte     This release of Binary II has a version 
                            number of $01.
+127    Number of Files to Follow
                   Byte     An appealing feature of Binary II is that 
                            a single Binary II file can hold multiple 
                            disk files, making it easy to keep a group 
                            of related files "glued" together when 
                            they're sent to a host.  This byte 
                            contains the number of files in this 
                            Binary II file that are behind it.  If 
                            this is the first file in a Binary II file 
                            containing three disk files, this byte 
                            would be $02.  The second disk file in the 
                            same Binary II file would have a value of 
                            $01 in this parameter, and the last would 
                            have value $00.  This count tells the 
                            Binary II downloading program how many 
                            files are remaining.  If any phantom files 
                            are included, they must be included in 
                            this count.

Filenames and Partial Pathnames

You can put a standard ProDOS filename or a partial pathname in the file 
information header (but never a complete pathname).  Don't use a partial 
pathname unless you've included, earlier in the Binary II file, file 
information headers for each of the directories referred to in the partial 
pathname.  Such a header must have its "end of file position" bytes set to 
zero, and no data blocks for the subdirectory file must follow it.

For example, if you want to send a file whose partial pathname is 
HELP/GS/READ.ME, first send a file information header defining the HELP/ 
subdirectory, then one defining the HELP/GS/ subdirectory.  If you don't, 
someone downloading the Binary II file won't be able to convert it because the 
necessary subdirectories will not exist.

Note:  GS/OS communication programs must use the slash (/) as the 
       pathname's separator in any partial pathname it puts in the 
       header.  Since GS/OS's standard separator is the colon (:), a 
       conversion may be necessary.

Filename Convention

Whenever a file is sent to a host, the host asks the sender to provide a name 
for it.  If it's a file in Binary II form, the name provided should end in 
.BNY so its special form will be apparent to anyone viewing a list of 
filenames.  If the file is compacted (using the public-domain Squeeze 
algorithm) before being converted to Binary II form, use a .BQY suffix 
instead.  If the file is a NuFX archive, use the suffix .BXY.

Identifying Binary II Files

You can determine, while transferring, if a file is in Binary II form by 
examining the ID bytes at offsets +000, +001, +002 and +018 from the beginning 
of the file.  They must be $0A, $47, $4C and $02, respectively.

Once Binary II files are identified, you can use the data in the file 
information header to create and open a ProDOS file with the correct name and 
attributes, transfer the file data in the Binary II file to the ProDOS file, 
set the ProDOS file size, then close the ProDOS file.  You would repeat this 
for each file contained inside the Binary II file.

Note:  The number of 128-byte blocks following the file information 
       header must be derived from the EOF attribute for the file.  
       Calculate the number by dividing the EOF by 128 and adding one to 
       the result if EOF is not 0 or an exact multiple of 128.  However, 
       if the file information header defines a subdirectory (the file 
       type is $0F), simple create the subdirectory file.  Do not open it 
       and do not try to set its size.

Ideally, all this conversion work will be done automatically by a 
communication program during file transfer.  If not, a separate conversion 
program (such as the previously mentioned Binary Library Utility, or BLU) must 
be used to do this for you.

Option_List Phantom Files

GS/OS will return, when asked, an option_list for files on many file calls.  
The option_list consists of a Word buffer length (which must be at least $2E), 
followed by a Word number of bytes GS/OS put in the buffer, a Word GS/OS file 
system identification, and the given number of bytes of FST-specific 
information (minus two; the count GS/OS returns includes the file system 

Option_list values are FST specific and contain values important to the native 
file system but not important to GS/OS.  For AppleShare, the option_list 
contains Finder Information, parent directory identification, and access 
privileges.  This information should be transferred with files.

Binary II uses a phantom file with identifier $01 $00 to indicate an 
option_list.  When this phantom file is seen, the contents should be used as 
the option_list for the file that immediately follows this file in the 
Binary II file.  The other attributes of the phantom file must be set to the 
same values as those for the file immediately following (the file for which 
the phantom file contains the option_list).  The EOF for the phantom file must 
be the size of the option_list + 2, and the file size must be adjusted 
accordingly to account for the phantom file ID bytes.

When receiving a Binary II file, the contents of this phantom file should be 
used as option_list input on a GS/OS SetFileInfo call.

If the GS/OS option_list returns a total of two bytes (just the file_sys_ID), 
there is no FST-specific information, and the option_list phantom file may 
safely be omitted.

The format of the option_list phantom file is as follows:

+000    Phantom ID 2 Bytes  The identifying bytes $01 $00.
+002    List Size  Word     The length of the bytes in the 
                            option_list, starting with the file system 
                            ID (the next word).
+004    FileSysID  Word     A GS/OS (not Binary II) file_sys_ID for 
                            the volume on which the file was stored.
+006    List Bytes Bytes    The bytes of the option list.  
                            There should be (List Size) of them, 
                            counting the previous word (FileSysID).

Extended File Considerations

Extended files contain two logical segments:  a data fork and a resource fork.  
These files can be created and manipulated by GS/OS, but not by ProDOS 8 or 
any other Apple II operating system.

When a GS/OS-based communication program sends an extended file, it must send 
it in the AppleSingle file format, preceded by a Binary II file information 
header.  (Such a program could easily convert an extended file to AppleSingle 
format on the fly.)  The Binary II header must contain the attributes of the 
AppleSingle file (including a file type of $E0 and an auxiliary type of $0001) 
and the "storage type code" field must be $01.  (The EOF positions for the 
data fork and resource fork of the extended file appear in an entry in the 
AppleSingle file header, not in the Binary II header.)

The AppleSingle format is described in Apple II File Type Note for File Type 
$E0, Auxiliary Type $0001.

A GS/OS-based communication program that receives an AppleSingle file can 
easily convert it on the fly to the extended file it defines.  ProDOS 8-based 
communication programs can only save the AppleSingle file to disk because it's 
not possible (nor is it encouraged to attempt) to create extended files with 
ProDOS 8 (without using block-level calls); a GS/OS based utility program is 
needed to convert the AppleSingle file to its extended form.

DOS 3.3 Considerations

With a little extra effort, you can also convert DOS 3.3 files to Binary II 
form.  This involves translating the DOS 3.3 file attributes to the 
corresponding ProDOS attributes so that you can build a proper file 
information header.

  o  Set the name to one that adheres to the stricter ProDOS naming 
     rules and put its length at +023 and the name itself at +024 to 
     +038.  Note that the name must be a simple filename and not a 
     pathname.  The actual DOS 3.3 filename must be placed at +039 
     (length) and +040 to +087 (name).  (DOS 3.3 actually restricts 
     filenames to 30 characters.)

  o  Set the ProDOS file type, auxiliary type and access to values 
     which correspond to the DOS 3.3 file type:

        DOS 3.3      ProDOS       ProDOS            ProDOS
        File Type    File Type    Auxiliary Type    Access
        $00 (T)       $04            $0000           $E3
        $80 (*T)      $04            $0000           $21
        $01 (I)       $FA            $0C00           $E3
        $81 (*I)      $FA            $0C00           $21
        $02 (A)       $FC            *               $E3
        $82 (*A)      $FC            *               $21
        $04 (B)       $06            **              $E3
        $84 (*B)      $06            **              $21
        $08 (S)       $06            $0000           $E3
        $88 (*S)      $06            $0000           $21
        $10 (R)       $FE            $0000           $E3
        $90 (*R)      $FE            $0000           $21
        $20 (A)       $06            $0000           $E3
        $A0 (*A)      $06            $0000           $E3
        $40 (B)       $06            $0000           $E3
        $C0 (*B)      $06            $0000           $21

        *  Set the auxiliary type for an A file to the
           memory address from which the program was saved.
           This is usually $0801.
        ** Set the auxiliary type for a B file to the
           value stored in the first two bytes of the the
           file (this is the default load address).

  o  Set the storage type code to $01.
  o  Set the size of file in blocks, date of creation, date of 
     modification, time of creation and time of modification all to 
  o  Set the end-of-file position to the length of the DOS 3.3 file, in 
     bytes.  For a B file (code $04 or $84), this number is stored in 
     the third and fourth bytes of the file.  For an I file (code $01 
     or $81) or an A file (code $02 or $82), this number is stored in 
     the first and second bytes of the file.
  o  Set the operating system type to $01.
  o  Set the native file type code to the value of the DOS 3.3 file 
     type code.

Attribute bytes inside a DOS 3.3 file (if any) must not be included in the 
data portion of the Binary II file.  This includes the first four bytes of a B 
(Binary) file, and the first two bytes of an A (AppleSoft) or I (Integer 
BASIC) file.

Further Reference
    o    GS/OS Reference
    o    ProDOS 8 Technical Reference Manual
    o    Apple II File Type Note, File Type $E0, Auxiliary Type $0001
    o    Apple II File Type Note, File Type $E0, Auxiliary Type $8002
    o    Apple II Miscellaneous Technical Note #14, Guidelines for 
         Telecommunication Programs

This document is Copyright by Apple Computer, Inc.