digital equipment corporation · maynard, massachusetts
       RT-11 Floppy Interchange Program

       Written by:
       Dick Murphy
       Digital Equipment Corporation
       Santa Clara, CA 95051

       User's notes

   This program is used to manipulate RT-11 floppy disk

file structures under OS/8. (RX01 ONLY, RX02 Not supported).

The operations available allow most of the functions of

OS/8 PIP to be simulated on the RT-11 disk. These

functions include:

       1. Creating a file on a RT-11 floppy

       2. Copying a file from an RT-11 floppy to an
          OS/8 device (disk, dectape, TTY:, LPT:, etc.)

       3. Deleting files from the RT-11 floppy

       4. Listing the directory of the RT-11 floppy

       5. ZEROing (INITing) the directory of a floppy
          to an empty state.

   The user interface is similar to the OS/8 command decoder.

When the program desires file specifications, it prints an

asterisk (*) and waits for input. The file specification line

is very similar to OS/8's. A sample input line is detailed



   The "*" is the prompt printed when the program wants input.

The name "RTFLOP.PAL" is the name of a file to be created on

an RT-11 floppy. The "<" character specifies that this is an

output file, and that the input file names are to follow.

The name "RTFLOP.PA" is the name of the OS/8 file to be read

to create the RT-11 file. The characters "/O" are an option flag

used to specify the operation to be performed. In this case,

they specify that the RT-11 file is an Output file.
   The general command line is of the form

*output<input/opt[/opt]....{$} or {return}

Where  "output" is an output file specification and "input" is

an input file specification. For an RT-11 file, the spec is a

file name, of up to six characters, a period, followed by an

extension of up to three characters. If there is o extension,

the period following the name can be omitted. The OS/8 file spec

uses the standard name format "device:file.ex" explained in the

OS/8 Handbook, page 1-45.

The "<" character is used to separate the output file from the

input file. If only an output file is to be specified, this

"<" character can be omitted.

   The file names are followed by at least one and possibly

several option flags. These are entered by typing a slash "/"

followed by the desired character, for example "/L".

The possible options are detailed later. If a "$", which could be

either a dollar sign, escape, or alt mode character, is used to

end the command line, it tells the program to return to the

OS/8 monitor when it is done processing this command. If an error

occurs while executing this command, however,the program will

prompt with another "*". If the command line is ended with a

return, the program will prompt with another "*" when it is

finished executing the command.

   While entering this command line, all the normal editing

functions of OS/8 can be used. Rubout deletes the last character

entered, and ^U (control-U) deletes the entire line. Line feed

causes the line being entered to be retyped.

   If a character is entered which the program does not

understand, the terminal bell rings and the character is

ignored. The OS/8 wildcard characters "*" and "?" are not

functional and are ignored. (See the OS/8 Handbook, page

1-55 for a description of wildcards).

       Functions available

   The function desired is entered in a command string

as a slash option of the form "/char" where "char" is a one-

character option flag. The available options are:

Option         Operation

 /O            Write RT-11 file
 /I            Read RT-11 file
 /L            List RT-11 directory
 /D            Delete RT-11 file
 /Z            ZERO RT-11 directory
 /0 (zero)     Select drive zero
 /1 (one)      Select drive one

   Only one option at a time can be performed; the last

option in the input string is the one executed.

(This limitation of one option switch does not include

the drive selection options, /0 and /1.)

/O Option - Write RT-11 File

   This option is used to create a RT-11 file from an

OS/8 device. The format of the command is:


   The items in braces ([]) are optional; if no device

is given for the OS/8 file, DSK: is assumed; if no drive

number is specified, /0 (left drive) is assumed.

   If a file with the same name as the file to be created

exists on the floppy already, it is deleted before the new

file is written. This means that if the new file cannot

be created due to an I/O error or size problems, neither

copy of the file exists. Sorry about that.

/I - Read RT-11 file

   This option is used to copy a file from an RT-11 device

to an OS/8 device.

   The command string is as follows:


   Again, the braces enclose optional items. If no OS/8

device is specified, DSK: is assumed. If a non-file structured

output device is specified (such as TTY: or LPT:) the file

name is not needed. If no unit switch (/0 or/1) is given, drive

zero (the left one) is assumed.

/L - List directory

   This option is used to list the directory of the RT-11

floppy. The listing is given in four columns. The first is

the name of the file, the second is it's size (in decimal),

the third is its starting block number (also decimal) and the

last column is the file's creation date.

   The format of the command string is:


   If no device is specified, TTY: is assumed. If only a file

name is entered, TTY: is still assumed. This means that an

explicit device name must be entered to cause a listing to

be written to a mass storage device, including DSK:.

   For example:

*LPT:/L                List on line printer
*DIR.DI/L      Lists on TTY:!
*DSK:DIR.DI/L  Creates listing file on DSK:
/D - Delete RT-11 file

   This option is used to delete a file from a RT-11 floppy.

This can be used to try to gain space to copy another file

to the floppy. The command string is:


/Z - Zero the floppy

   This option writes a new directory on the floppy with

one empty file. This is necessary if yours is a new floppy

or if it has an OS/8 directory. The command string is:


   To be sure that this is what you want, the program asks:

Zero - are you sure?

   Respond with "Y" if you want a new directory.

       General information

   This program requires 8K of memory to run. The program

itself resides in field zero, field one is used for buffers,

message storage, and the like.

  Assembly instructions:

Type the following:

.SAVE dev RTFLOP=2401

   This program will run under BATCH. The commands should

be entered into the batch stream as one normally does.

   This program does not recognize wildcards. Therefore, a

command such as :

is illegal. However, There are two TECO macros distributed

with this program which allow one to approximate this function.

The first macro writes files to a floppy, the second reads files

from a floppy.

       RTOUT.TE - Writing files to a floppy

   This macro reads a file with a list of file names and creates

a BATCH stream to write the files to a floppy. The format of the

entries in this file is:

nameyy.ex .....

Where each "name" is padded with blanks, if necessary, to six


   The DIRECT command can be used to create this file. For example,


creates a file called FILE.DI with the desired directory listing.

The "=1" is necessary to insure a one-column listing. Giving

this file to RTOUT will copy all files with a .BN extension to

a floppy.

   To execute RTOUT, enter a MUNG command:

   .MUNG RTOUT,file

   where "file" is the name of the directory listing file. If

no extension is entered, .DI is assumed (this is what DIRECT uses).

   To copy all the .PA files on RKB0: to a floppy, type the commands


   When the macro gets started, it will ask you to "Enter desired

extension:". At this time, enter the extension (three characters)

that you would like to give to the files to be created on the floppy.

Only the first three characters are significant. A rubout will echo

and delete the last character typed.

   When the macro asks you to "Enter input device:", enter the

OS/8 name of the device on which the files are stored. This

device name must be followed by a colon (:). If the device is DSK:,

simply hit return.

   For RTOUT to function, both TECO.SV and BATCH.SV must reside

on SYS:. If your copy of TECO does not have all of the latest

patches, RTOUT will most likely fail.

   Another macro is provided which provides the converse function

to RTOUT. This macro copies files from a floppy to an OS/8 device.

This macro, RTIN, is quite similar to RTOUT.

   To copy all the files from a floppy to an OS/8 device:

   *FLOP.DI/L$                 (generate a directory listing)
   .MUNG RTIN,FLOP             (call RTIN)
   Enter desired extension:RT  (enter the extension)
   Enter output device:RKB0:   (put the files here)

   This copies all files from drive zero to RKB0:, with

an extension of .RT. The directory listing file (FLOP.DI)

could have been edited before the MUNG in order to copy

only some of the files on the floppy.

       Error messages

-Bad slash option
       The character following a "/" was not one of the
       following: I, O, L, Z, D, 1, 0.

-No option flag
       No option was specified

-Bad directory
       The directory on the floppy has an invalid
       structure. (possible an OS/8 directory)

-No Input file
       Both input and output files were required, but
       no "<" separator character was found.

-Handler fetch failed
       An attempt to fetch the OS/8 handler specified
       failed. This usually means that a non-existant
       device was specified.

-OS/8 I/O Error
       An I/O error ocurred reading or writing the OS/8

-Cannot specify RT-11 device
       A device specification (e.g. RXA0:) was found
       in the RT-11 name. This is illegal. Use /0 and /1
       to specify drives.

-Need file name
       A file structured OS/8 device was specified for
       input or output without giving a file name.

-Out dev full
       The OS/8 output device did not have sufficient empty
       space for the directory listing.

-OS/8 File overflow
       The empty space on the OS/8 device was too small
       to hold the output file. SQUISH or try another device.

-File not found
       The file specified could not be found

-Segment full (SQUEEZE floppy)
       The last open segment of the RT-11 directory is full.
       RTFLOP cannot create a new file on this floppy. A
       SQUEEZE under RT-11 may fix this.

-No room on floppy
       There was not enough room on the floppy for the output
       file. SQUEEZE or delete files to create room.

-Floppy I/O error
       An input or output error ocurred on the floppy.
       Read errors are retried eight times before this message.
       Write errors fail immediately.

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