home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Simtel MSDOS 1992 September
/
Simtel20_Sept92.cdr
/
msdos
/
printer
/
vspool.arc
/
SPOOL.DOC
next >
Wrap
Text File
|
1989-03-20
|
30KB
|
859 lines
Table of Contents
1. Overview...................................................2
2. Installation...............................................2
3. Accessing Versa-Spool Once Installed.......................3
4. The Parameters Enumerated..................................4
5. Examples...................................................7
5.1. To Install............................................8
5.2. After Installation....................................8
6. Programmer's Corner........................................9
6.1. Sub-Function 0 : Return Signature.....................9
6.2. Sub-Function 1 : Toggle Pause.........................9
6.3. Sub-Function 2 : Clear Buffer.........................9
6.4. Sub-Function 3 : Request Pause Condition..............9
6.5. Sub-Function 4 : Request Free Buffer Space............9
6.6. Sub-Function 5 : Request Total Buffer Size............9
6.7. Sub-Function 6 : Redirect Output To LPT1:.............9
6.8. Sub-Function 7 : Redirect Output To LPT2:.............9
6.9. Sub-Function 8 : Redirect Output To LPT3:.............9
6.10. Sub-Function 9 : Request Output Device..............10
6.11. Sub-Function A : Request Output Speed...............10
6.12. Sub-Function B : Request Device Spooled Status......10
6.13. Turbo Basic Function Call Examples..................10
7. Business Stuff............................................10
8. User Registration Form....................................12
i
Versa-Spool
Version 1.01
A multi-printer spooler
Copyright 1989 - Jeff Newbro
1
1. Overview
Versa-Spool is an extremely versatile print spooler written for
the IBM-PC/AT series of computers. In an effort to anticipate
all the circumstances under which Versa-Spool may be required to
operate, features such as multiple buffers, large buffer size,
adjustable output speed, and the ability to redirect a printer
stream from one printer to another have been implemented. A
protocol has been developed which will permit access to the
operating parameters and current status of Versa-Spool either
from the dos prompt, or from within a program in order to enable
applications to interact intelligently with their printer
resources.
Versa-Spool is installed and accessed at the dos prompt with the
following syntax :
SPOOL [-option(s)] <enter>
where option is one or more of the following :
-b{n} = Buffer size (n=1..Available memory in k)
-c = Clear print buffer
-n{n} = printer Number (n=1..3)
-p = toggle Pause
-r{n} = Redirect output to new device (n=1..3)
-s{n} = output Speed in cps (default = 100)
-u{n} = allocate buffers in Unused memory (n=0..FFFF)
-v{n} = offset interrupt Vectors (n=1..6)
-? = Show status
2. Installation
Versa-Spool is a memory resident program which installs itself
according to parameters specified by the -b, -n, -s, -u, and -v
options the first time it is executed. If no value is specified
for these options, Versa-Spool will assume that 1 buffer, 1
kilobyte, and 100 characters per second, are the desired
parameters.
For example, to install Versa-Spool to provide LPT1: and LPT2:
with 80k buffers each, the following command line would be
entered :
C:\> spool -n2 -b80 <Enter>
or, for a single 200k buffer for LPT1:, type :
C:\> spool -n1 -b200 <Enter>
It would not be possible to install a single buffer for LPT2:,
since the buffers are allocated sequentially, beginning with
2
LPT1:. It would, however, be possible to install a single buffer
for LPT1: whose output was redirected to LPT2:. This would be
accomplished by the following two commands :
C:\> spool -n1 -b100 <Enter>
C:\> spool -n1 -r2 <Enter>
The redirection feature will be discussed in greater detail
later.
Once Versa-Spool has installed itself as a terminate and stay
resident program (TSR for short), it will print its installation
status on the screen and return to dos. For those who may want
to install Versa-Spool with a batch files that checks the success
of its commands, an error level of 0 will be returned if the
installation was successful, or 1 if there was an error. Also,
for the batch file programmers, the messages printed on the
screen by Versa-Spool may be piped to the nul device if it is
undesirable for the end user to see them. For instance a batch
file containing the lines :
.
.
spool -n1 -b100 > nul
IF ERRORLEVEL 1 GOTO NOGOOD
.
.
would install a 100k buffer for LPT1: and show no message after
installation. If Versa-Spool did not install itself properly,
execution would be vectored to the label "NOGOOD", presumably to
echo an error message and exit.
Subsequent executions of Versa-Spool will not install another TSR
copy of Versa-Spool, but will rather provide communication with
the already installed TSR program. The protocol for this
communication is described in the "Programmer's Corner" section.
3. Accessing Versa-Spool Once Installed
After the first time Versa-Spool is run, and its TSR portion is
loaded, subsequent executions of the program will either cause it
to print the current status of the resident copy in response to
the -? option, or attempt to modify its operating status
according to the -c, -p, or -r parameters.
For example, if LPT2: is to be paused for some reason, the line :
C:\> spool -n2 -p <Enter>
would be entered. Note that in this instance, the -n parameter
3
specifies the device to be addressed, rather than the number of
buffers to be installed. This convention applies to all
executions of Versa-Spool subsequent to the first, when it
installs its TSR portion. The pause option is a toggle, so to
restart the printer, the same line would be re-entered.
Similarly, to clear the buffer for LPT1:, the line :
C:\> spool -n1 -c <Enter>
will effect the desired result. Or, since -n1 is a default
value, simply :
C:\> spool -c <Enter>
would suffice.
4. The Parameters Enumerated
Now that you have the general idea, here is some more specific
information about the available parameters.
-b This parameter is only available when installing Versa-
Spool. Most currently available spoolers are limited
to 64k, but Versa-Spool permits buffer sizes between 1k
and the maximum available memory in your machine (less
64k) to be installed. When allocating buffers with the
-u parameter, the buffer size is restricted by other
factors which will be discussed later, but in most
situations the previously stated rule applies. During
installation, the default value for this parameter is
1k, and after installation, it cannot be used to modify
the TSR portion of Versa-Spool.
-c The buffer selected by the -n parameter will be
cleared. Any other buffers which have been allocated
will continue to function without disturbance. A
typical command line would be :
C:\> spool -n2 -c
which would clear the contents of the buffer for LPT2:.
This parameter has does not function during
installation, but the clearing of a buffer is implicit
in the process of its creation.
-n During installation, the -n option specifies the number
of buffers that will be allocated. Each will be the
same size, as specified by the -b option, and will be
assigned sequentially to LPT1:, LPT2: and LPT3:. Thus,
it is not possible to assign a buffer for LPT2: without
4
first assigning one for LPT1:. Once the resident
portion of Versa-Spool is installed, the -n parameter
will serve to specify the buffer to which any commands
will apply. For instance, in order to request the
status of the buffer for LPT3:, the following line
would be typed :
C:\> spool -n3 -?
When the -n parameter is not specified, either 1
buffer, or LPT1: will be assumed during installation or
subsequent operations, respectively.
-p Once Versa-Spool is installed, a printer may be paused,
if that is desirable. The -p option, which effects
this action, is a "toggle" and invoking it will cause a
printing device to pause, or a paused device to resume
printing.
-r Once installed, the output from the spooler may be
redirected from its normal device to another LPT:
through the use of this parameter. Thus, if you had a
dot-matrix printer attached to LPT1:, and a letter
quality printer attached to LPT2:, and a word processor
that only printed to LPT1:, you could redirect the word
processor output to LPT2: through the use of this
option. The command line for that specific situation
would be :
C:\> spool -n1 -r2 <Enter>
Also, in database applications where printer speed is a
problem because large reports are generated regularly,
Versa-Spool may be used to divide the output between
two or three printers to afford an effective output
rate of two or three times that possible with a single,
unspooled printer.
The -r option is only available after the resident
portion of Versa-Spool has been installed, and has no
effect during installation.
-s The output speed parameter determines the efficiency of
Versa-Spool for the environment in which it is being
used. Since Versa-Spool shares the computer's
attention with the currently running application, there
is a compromise between the rate at which it sends data
to the printer(s), and the rate at which it permits the
currently running application to perform its functions.
Outputting data to the printer at a rate faster than
either the computer can process it, or the printer can
accept it will result in Versa-Spool hogging the
5
computer's time to no advantage, and causing the
application program to seem unresponsive. Outputting
too slowly, of course will cause large documents to
take excessive amounts of time to print. Since the
circumstances under which Versa-Spool may be expected
to vary widely, this parameter has been made accessible
to the user. This parameter is adjustable from 20 to
16000 characters per second, in increments of 20 cps.
It will be some time before hardware is available that
will accommodate the higher speeds, but Versa-Spool
will be ready when the time comes.
-u Although dos was only written to accommodate 640k of
main memory, many machines are currently being produced
which permit 1000k (1 megabyte) to be installed on
their motherboards. The additional 360k of memory,
beginning at hex segment A000 is partially allocated to
video board RAM, extended memory buffers, and other
such functions, but there is frequently 64k or more of
contiguous space available in this area. With the -u
option, Versa-Spool may be installed with its buffers
allocated in this unused area, allowing large buffers
to be implemented while taking up less than 30k of
precious dos space. It is not recommended that the
naive user try to install Versa-Spool in this
configuration, but someone with light programming
experience should be able to find between 64k and 192k
of unused RAM in the range of segments C000 to F000 in
one of these 1 megabyte machines. Once found, Versa-
Spool may be instructed to allocate its buffers
starting at a given segment address by entering the -u
parameter followed by the HEX address of the segment.
Segment addresses of less that A000 will be adjusted
upward to A000, and if Versa-Spool does not find RAM at
the specified segment, an error message will be
displayed and the resident portion will not be
installed. A typical implementation of such a buffer
would be :
C:\> spool -n1 -b128 -uD000 <Enter>
Just to make it a little easier for the stout at heart
who decide to try this, there should be 64k available
starting at E000 in nearly all of these machines and
128k starting at D000 in most without extended memory.
It is worth checking below that area, but many hard
disk controllers have a ROM starting at C800 which will
interfere with the buffer.
-? If it is desirable to know the status of one of the
spooled printers, this parameter will instruct Versa-
Spool to display a detailed report on the screen. This
6
information includes any redirection for the device,
the output speed, buffer size, port status, pause
status, and remaining free space. This function may
also be useful to programmers, as it returns the
remaining free space (in k) to dos as an error level
when it executes. Thus it may be used in batch files
to test for insufficient buffer space before running a
program which generates large reports. An example from
a batch file which does this follows :
.
.
:START
REM Get the free space in buffer 1 (send the
REM display to nowhere)
spool -n1 -? > nul
REM If there is 10k or more of free space, print
REM the next file
IF errorlevel 10 GOTO PRINTDOC
REM Do some word processing until the spooler
REM is ready
wordproc %2
:PRINTDOC
REM Print the report specified by %1
printrep %1
:NEXT
.
.
Of course, this option is only available once the
resident portion of Versa-Spool is installed and has no
effect during installation.
-v Many TSR programs use one or more of the interrupts
between 60h and 67h for their resident functions. So
that the two interrupts required by Versa-Spool do not
contend with any of the programs that you normally keep
resident, you may install it with its vectors offset
from the default 60h and 61h through the use of this
parameter. The example command line :
C:\> spool -n1 -v3 <Enter>
would install Versa-Spool with its interrupts at 63h
and 64h. This option is only available during
installation, and will default to 0 if not specified.
5. Examples
Here are a few more example command lines to help convey the
7
points expressed earlier.
5.1. To Install
Command Configuration
C:\> spool Show syntax for Versa-Spool
but do not install.
C:\> spool -N2 -B60 Install Versa-Spool with 60k
100cps buffers for LPT1: and
LPT2:.
C:\> spool -n1 -b350 Install a 350k, 100cps spooler
for LPT1:.
C:\> spool -n1 -b128 -uC800 Install a 128k, 100cps spooler
for LPT1: with its buffer
starting at hex segment C800.
C:\> spool -s256 -n1 -s200 Install a 256k, 200cps spooler
for LPT1:.
5.2. After Installation
Command Effect
C:\> spool -N1 -? Show the current status of
LPT1:
C:\> spool -n1 -c Clear the buffer for LPT1:.
C:\> spool -P -N2 If LPT2: is printing, it will
pause, otherwise, it will
resume printing.
C:\> spool -n1 -r2 Redirect the output of logical
LPT1: to physical LPT2:.
Note that the parameters are neither case-sensitive, nor required
to be in any specific order. Thus, the lines :
C:\> spool -n1 - C
and
C:\> spool -c -N1
are equivalent. Also, throughout the documentation, the prompt
indicates that the current directory is C:\, although this is by
8
no means required for the proper operation of the program.
6. Programmer's Corner
When Versa-Spool is installed, it changes the original interrupts
17h and 1Ch to 60h and 61h (plus an offset, if any),
respectively, and installs its own interrupt handlers for 17h and
1Ch. The new interrupt 1Ch performs Versa-Spool's background
functions and then passes control to the original interrupt 1Ch.
The new interrupt 17h performs a reset (function 2) immediately
by passing control to the original interrupt 17h. All other
functions are buffered by Versa-Spool. The new interrupt 17h
also has an additional function not provided by the original
interrupt, which may be called from a high level program to
request the spooler status or control the operation of the
spooler. The additional function and its sub-functions are
implemented as follows :
In all cases :
Interrupt = 17h
AH = 3 ( Function # )
AL = Sub-Function # ( Sub-Function # )
DX = Device # (0..2) ( LPT1:..LPT3: )
6.1. Sub-Function 0 : Return Signature
Return Value : AX = 1234 if Versa-Spool is installed,
undefined if not installed.
6.2. Sub-Function 1 : Toggle Pause
Return Value : AX = 1 if paused, 0 if resumed.
6.3. Sub-Function 2 : Clear Buffer
Return Value : AX = 0 if cleared, 302h if not.
6.4. Sub-Function 3 : Request Pause Condition
Return Value : AX = 1 if paused, 0 if resumed.
6.5. Sub-Function 4 : Request Free Buffer Space
Return Value : AX = Remaining Buffer Space (in Kbytes).
6.6. Sub-Function 5 : Request Total Buffer Size
Return Value : AX = Total Buffer Size (in Kbytes).
6.7. Sub-Function 6 : Redirect Output To LPT1:
Return Value : none.
6.8. Sub-Function 7 : Redirect Output To LPT2:
Return Value : none.
6.9. Sub-Function 8 : Redirect Output To LPT3:
Return Value : none.
9
6.10. Sub-Function 9 : Request Output Device
Return Value : AX = Output Device To Which Selected Device
is printing (0..2).
6.11. Sub-Function A : Request Output Speed
Return Value : AX = Output Speed in Characters per second.
6.12. Sub-Function B : Request Device Spooled Status
Return Value : AX = 1 if device is spooled, 0 otherwise.
6.13. Turbo Basic Function Call Examples
The following Turbo Basic1 code will illustrate the use of some
of the previous functions. The same principles exemplified here
will apply to all languages that permit interrupt calls.
.
.
REG 1, &H304 ' AH = 3 AL = 4 (Function 3, Sub-
' Function 4)
REG 4, &H0 ' DX = 0 (LPT:1)
CALL INTERRUPT &H17 ' Call the interrupt
PRINT "The buffer for LPT1: has ";REG(1);"k free"
REG 1, &H304 ' AX = 304h
REG 4, &H1 ' DX = 1 (LPT:2)
CALL INTERRUPT &H17 ' Call the interrupt
PRINT "The buffer for LPT2: has ";REG(1);"k free"
REG 1, &H307 ' AX = 307h
REG 4, &H0 ' DX = 0
CALL INTERRUPT &H17 ' Call the interrupt
PRINT "The data sent to LPT1: will now be output to LPT2:"
.
.
7. Business Stuff
This program is distributed under the ShareWare concept. Under
this philosophy you may run the program for the purpose of
evaluation for a reasonable period of time without incurring any
liability either to purchase a license or be held responsible for
any copyright violations. If you decide that the program does
suit your purposes, however, you are obliged to purchase a
license to use it and pay a registration fee. When you register
your program, you will receive your own serialized copy which
--------------------
1. Turbo Basic is a registered trademark of Borland International
10
will probably earn you money, since a commission of 25% is paid
to the licensee whose serial number appears on each registration
form received. Thus, if you upload your copy to a bulletin board
and five people download it and register as licensees, you will
not only have acted in good faith, but made money for having done
so. These commissions are paid at the end of each month.
Now that your interests are protected, the license to use Versa-
Spool is issued subject to the conditions specified on the
registration form, which protect mine.
Thank you for your interest in Versa-Spool and I hope you enjoy
using it as much as I enjoyed writing it for you.
11
8. User Registration Form
Licensing Conditions
No warranty is either expressed or implied with regard to Versa-
Spool. The user has more than ample opportunity to evaluate the
performance of the program under normal operating conditions, and
the author cannot be expected to bear the consequences of an
improper evaluation. Further, the author will be held blameless
for any and all damages arising from the use of Versa-Spool, be
they direct or consequential.
Name :______________________________________________________
Title :_____________________________________________________
Company :___________________________________________________
Address :___________________________________________________
City,State,Zip :____________________________________________
Business Telephone :________________________________________
Serial number of evaluation Versa-Spool :___________________
Where did you obtain the evaluation copy ?
(BBS, Consultant, Magazine, other) : _______________________
I have read and agree to the terms of the license agreement :
________________________________________________ ___/___/___
(Signature) (Date)
Comments or suggestions :___________________________________
____________________________________________________________
____________________________________________________________
Please complete the above form and send it with your check or
money order for $20 (plus appropriate sales tax in MA) to :
Jeff Newbro
267 Lexington Street
East Boston, MA 02128
Assigned Serial # :_________________________ (For office Use)
12
