Network print system for allowing a printer or printers to select a host

A network print system includes a host having the function to generate print data, a printer that processes printing on the basis of a specified print data, and a communication network that connect the printer and the host so that they can communicate with each other. The printer of the network print system carries out send request of desired print data to the host, and receives print data corresponding to the send request, and thereby executes print processing in accordance with the print data. Further, the host includes a memory to store the print data, and sends the print data stored in the memory to the printer that has carried out a send request of print data when the send request of the print data is carried out in the printer through the communication network.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a network print system to output images 
including documents and the like prepared by a computer connected on a 
network such as LAN or so by use of an optional printer connected on the 
same network. 
2. Description of the Related Art 
Recently there are many network print systems to output images made by 
computers in a configuration of a network environment such as LAN 
involving plural computers and plural printers. 
In the network print systems in the prior art, at the event of image data 
created (a print job) by a certain computer so as to be printed by a 
printer, the print job was immediately sent to the printer designated on 
the network or a print server to store and control the print job. 
In each printer or print server, the received print job is stored initially 
into a First-In First-Out (FIFO) print queue consisting of a buffer memory 
and the like, and a print job that has come first into the print queue is 
printed first. 
In this manner, in the print job management methods by the conventional 
network print systems, at the event of a print job on a computer, the 
print job is sent to a printer or a print server set on the network as 
print data. Accordingly, there were many cases where many print jobs were 
accumulated in a certain printer or print server designated on the 
network, even though print queues of other printers were empty. 
Furthermore, in each printer or print server, print jobs were executed in 
the sequence of coming into the print queue, therefore, even a print job 
of one sheet had to wait in the case when another print job of numerous 
sheets had come into the print queue of the printer just before it. 
Namely, printing was executed always by a predetermined printer, so even 
when there were other printers ready for printing, a user who wanted to 
print out only one sheet had to wait for a long time, which was one of the 
negative effects in the prior art. 
Still further, since printing was executed in the sequence of print jobs 
coming into a print queue of the printer or print server, when plural 
users utilized a single printer, they may have left their own printed 
matters in that printer. Namely, the information of printed matters may 
have been accessed by other persons, as a result, it was difficult to keep 
secrecy, which was another problem in the prior art. 
Also, print jobs were controlled at the printer side, and the contents of 
the print queue were printed at once, therefore, if printed matters were 
output by mistake, unnecessary printed matters were output automatically. 
Moreover, it was very difficult to completely delete a print job created 
by mistake from the computer side, which was another problem in the prior 
art. 
And further, when plural copies of an identical document were necessary, 
for instance, in a conference or so, in the conventional network print 
system, it was necessary to copy the printed matter output by the printer 
by use of a photoelectric copying machine or to execute the same print job 
many times. 
SUMMARY OF THE INVENTION 
Accordingly, the object of the present invention is to provide a network 
print system that enables to reduce the print waiting time, to eliminate 
printing mistakes, to enhance the secrecy function of printed information 
in a shared printer, and further for designated plural people to obtain an 
identical document from optional printers in a network such as LAN and so 
on. 
According to the present invention, provided is a network print system 
having a host that has a function to generate print data, a printer that 
carries out printing on the basis of specified print data, and a 
communication network that connects the printer and the host so that the 
printer and the host communicate with each other, wherein printing is 
executed by the printer on the basis of print data transmitted from the 
host, the network print system comprising the printer including: means for 
requesting to the host to be transmitted a desired print data from the 
host to the printer; and means for printing a document based on the 
desired print data sent from the host; the host including: means for 
storing the print data; and means for transmitting the print data stored 
in the storing means to the printer via the communication network in 
response to the request by the requesting means. 
Other objects and advantages of the present invention will become apparent 
from the detailed description to follow taken in conjunction with the 
appended claims.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The invention is described in detail by reference to the following 
referential examples and preferred embodiments wherein. 
FIG. 1 is a schematic diagram showing a configuration of network print 
system of one embodiment of the present invention. In FIG. 1, plural 
computers C1, C2, and C3 as host, and plural printers P1 and P2 are 
connected with one another through communication network N. This network 
print system is so designed that users 1, 2, and 3 having respective 
identification information (ID or so) can use the system. 
Each of computers C1, C2 and C3 prepares documents and so on by use of 
various application software. Computers C1, C2 and C3 are connected to 
auxiliary memories D1, D2 and D3 respectively. Especially, image data 
(hereinafter referred to as print data or print content data) prepared for 
the purpose of printing by either of printer P1 or P2 are stored into 
these auxiliary memories D1, D2 and D3. 
All the computers C1, C2 and C3, and printers P1 and P2 connected on the 
network N execute the management processing of print jobs that have 
occurred at each of the computers C1, C2 and C3, under the control of CPUs 
arranged therein respectively, and in accordance with a print job 
management program stored in memories arranged therein respectively, 
through mutual communications among computers C1, C2 and C3, and printers 
P1 and P2. 
Each of the printers P1 and P2 has a display means such as a display unit, 
and input means such as a mouse, keyboard and the like to select specified 
items and to enter a password or so on the basis of displayed contents. 
Herein, when documents are prepared by the computers C1, C2 and C3 for the 
purpose of printing by either the printer P1 or P2, and the documents are 
stored into the auxiliary memories D1, D2 and D3 respectively, which is 
called "Event of Print Jobs". 
Next, the data configuration of print jobs to be stored into the auxiliary 
memories D1, D2 and D3 is explained hereinafter in reference to FIG. 2. 
A print job includes print job management data and print content data. 
And further, the print job management data includes "Job ID", "Job 
Generator ID", "Job Event Date and Time", "Job Effective Term", "Job 
Retain Computer ID", "Job Ownership", "Job Reproduction Number", 
"Password", and "Print Content Index". 
The print content data includes printer management data relating printed 
matter, and content data such as documents prepared by the computers C1, 
C2 and C3 for the purpose of printing out. 
"Job ID" is added at the event of print job to identify it, and is peculiar 
to each print job; therefore, it cannot be changed. 
"Job Generator ID" is added at the event of print job to identify the 
generator of the print job. This "Job Generator ID" is peculiar to each 
print job; therefore, it cannot be changed. 
"Job Event Date and Time" shows the date and time of the event of print 
job, and once added, it cannot be changed. 
"Job Retain Computer ID" shows the identification data (ID) of a computer 
where the print job is generated at the event of print job, and is used to 
know in which computer's auxiliary memory a print job is retained. This 
"Job Retain Computer ID" cannot be changed too. 
"Job Ownership" shows who the owner of a print job is, and normally, the ID 
or name of print job generator is recorded at the event of print job. "Job 
Ownership" may be changed by use of a print job management program. 
Namely, a single print job may be owned by plural users by adding other 
person's ID or name. 
"Job Reproduction Number" shows the number of copies of printed matter that 
may be obtained from one print job. "Job Reproduction Number" corresponds 
to the number of job owners; therefore, it cannot be rewritten. 
"Password" is used to judge whether the owner of print job preset as "Job 
Ownership" is identical with executor of printing or not. This "Password" 
may be set and changed by its print job generator by use of the print job 
management program. 
"Job Effective Term" shows the effective term of print job on the network 
N, i.e., the term when printing is available. The purpose of defining this 
job effective term is to prevent the auxiliary memories D1, D2 and D3 from 
becoming full of jobs, and also to keep secrecy. This setting is made by 
use of the print job management program. 
"Print Content Index" allows one to add a simple explanation for users to 
identify what the printed matter obtained from the print job is. "Print 
Content Index" may be described by use of the print job management 
program. 
Then, the outline of the functions of the print job management program is 
explained hereinafter in reference to FIG. 3. The print job management 
program is to manage print jobs by use of the above print job management 
data. 
The print job management job regards a print job as completed when "Job 
Reproduction Number" becomes "0" or when "Job Effective Term" passes. 
However, the print job completion by "Job Effective Term" passing has 
priority over the print job completion by "Job Reproduction Number" 
becoming "0". Also, a print job generator may delete a print job of its 
own generating at any time. 
The print job management program is so designed as to display the detailed 
data of print jobs of the computers C1, C2 and C3 on which the print job 
management program is running on display units of the computers C1, C2 and 
C3. It also displays the remaining memory capacities of the auxiliary 
memories D1, D2 and D3 in the computers C1, C2 and C3, a list of printers 
that can output desired print data, and also it collates password when a 
print job execution request is sent from either of the printer P1 or P2 
through the communication network N, and also informs a user of a the 
event of print job addressed to that user. 
First, the user 1 prepares documents or so on at the computer C1, to 
generate print job J1 (arrow (1) in FIG. 3). At this moment, the user 1 
may enter the items of "Job Ownership" and "Password" of the print job 
management data, give the ownership of that print job to other users than 
the user 1, and enter the items of "Job Effective term", "Print Content 
Index" and so on. 
The print job J1 generated in this manner has a structure shown in FIG. 2, 
and the generated print job J1 is stored under control of the print job 
management program. 
Next, the print job J1 is not immediately sent to printers on the network 
N, but is stored into the auxiliary memory D1 of the computer C1 where 
that print job J1 has been generated (arrow (2) in FIG. 3). 
At this moment, if the data amount of the print job J1 is larger than the 
remaining memory capacity of the auxiliary memory D1 of the computer C1, 
then the print job management program gives a warning that the auxiliary 
memory capacity is low to the user 1 who has generated the print job J1, 
and makes the generated print job J1 invalid. 
In this manner, the control of the memory capacities of the auxiliary 
memories D1, D2 and D3 by the print job management program enables to 
generate many print jobs by the same computers C1, C2 and C3 and to keep 
plural print jobs J1 through J5 in their respective auxiliary memories D1, 
D2 and D3 so long as the memory capacities of auxiliary memories D1, D2 
and D3 permit. 
When print execution is instructed from, for example, the printer P1 
connected to the communication network N (arrow (3) in FIG. 3), the 
computer C1 sends out the print job J1 (arrow (4) in FIG. 3) for the first 
time, and the printer P1 receives it and starts printing (arrow (5) in 
FIG. 3). 
The print job management data of the print job J1 should be changed only at 
the computer C1 where the print job J1 is generated, and only by the 
generator of the print job J1, that is, the user 1. 
When to change the contents of the print job management data, for example, 
the generator of the print job J1, at the computer C1 where the print job 
J1 is generated, starts the print job management program, and enters 
desired data under the control of CPU in accordance with the program and 
by use of a keyboard, mouse, or the like. On the basis of the entered 
data, the contents of the print job management data stored in the 
auxiliary memory D1 are rewritten. 
The print job management program does not adopt the print job queuing 
method as seen in the conventional printer server, but can send print jobs 
in response to the print job send request from the communication network N 
irrespective of the occurrence sequence of print jobs. 
In this way, the print job J1 is kept in the auxiliary memory D1 and 
controlled by the computer C1 by use of the print job management program, 
so the print job J1 may be printed out by both the printer P1 and P2 
connected to the communication network N, and user may execute a printing 
job by either of the printer P1 or P2 which is not busy and ready for 
printing. As a consequence, since the user selects a printer, which is not 
busy, waiting time may be reduced. 
The print job J1 generated at the computer C1 is kept in the auxiliary 
memory D1 of the computer C1, and the generator of the print job J1 may 
delete the print job J1 at any time at necessity; therefore, erroneous 
output to the printer may be prevented. 
Next, the circuit configuration of the printers P1 and P2 employed in the 
network print system under the present invention is explained hereinafter 
in reference to FIG. 4. 
The printers P1 and P2 are connected via a network interface circuit 10 to 
the network N. The network interface circuit 10 is connected to a CPU 12 
via a system bus S1. A ROM 14 containing the control program, a RAM 16 
that runs the control program contained in the ROM 14, and an NVRAM 18 
that contains list data and the like of the computers C1, C2, and C3 on 
the network N are connected to the CPU 12 via the system bus S1. Further, 
via the system bus S1, a display 20 that includes a liquid crystal panel 
and so on, an input device 22 that includes a keyboard, mouse or touch 
panel for a user to enter data, a card reader 24, a dual port RAM 26 that 
carries out status communications with a printer CPU 5a (FIG. 5) to 
control the printer, are connected to the CPU 12. 
The network interface circuit 10 and a page memory 28 are connected with 
each other through a high speed image bus S2. The page memory 28 is 
connected via the system bus S1 to the CPU 12 too. Further, this page 
memory 28 is connected via the high speed image bus S3 to a modulator 
circuit 5w shown in FIG. 5. 
In reference to FIG. 5, the hardware configuration of the printer mechanism 
portion 5 of the printers P1 and P2 is explained hereinafter. To a printer 
CPU 5a of the printer mechanism portion 5, a main motor driver 5c to drive 
a main motor 5b, a driver 5e to drive and control a sensor, switch, 
solenoid and the like, and a fixer lamp controller 5g to control a fixer 
lamp 5f are connected respectively. A main charger 5h, a transfer charger 
5i, a separation charger 5j and a charge remover 5k are connected to a 
high power output controller 5m via high power transformers 511, 512, 513 
and 514 respectively, and this high power output controller 5m is 
connected to the printer CPU 5a. Further to the printer CPU 5a, a 
discharging lamp controller 5o to control a discharging lamp 5n, and a 
paper supply controller 5s to control a paper supply motor 5r are 
connected. Connected to the paper supply motor 5r are a paper supply 
roller 5p and a pickup roller 5q. 
A laser diode 5t and a polygon mirror motor 5u are connected to a laser 
driver 5v, which is connected to the printer CPU 5a via a modulator 5w. 
Image data that is sent from the page memory 28 shown in FIG. 4 via the 
high speed image bus S3 is input to the modulator 5w. On the basis of the 
image data input to the modulator 5w, the image is printed onto a 
specified paper sheet by the control of the printer CPU 5a. 
Then, in reference to the flowchart shown in FIG. 6, operation processes by 
the print job management program in the network print system in FIG. 1 are 
explained hereinafter. Herein, especially explained is the case when the 
ownership of a print job is owned by the generator of the print job 
concerned. 
In FIG. 6, in the step S601, a user generates some print jobs (print job J1 
through print job J5) by the computer C1. 
In the step S602, generated print jobs J1 through J5 are stored into the 
auxiliary memory D1 of the computer C1 where they have been generated, as 
mentioned previously. That is, when plural documents are created for the 
purpose of being printed, they are stored into the auxiliary memory D1 as 
the print content data of print jobs J1 through J5. 
And, herein, the ownership of the print jobs J1 through J5 is owned by only 
the user who has generated the print jobs concerned, therefore, there is 
no need to change the "Job Owner ID" and "Password" to be stored in the 
auxiliary memory D1 per each of print jobs J1 to J5 as print management 
data. As a corollary, the "Job Owner ID" and "Password" to be stored in 
the auxiliary memory D1 per each of print jobs J1 to J5 as print 
management data are those of only the user concerned. Further, at 
necessity, "Job Effective term", "Print Content Index" and so on may be 
entered as print job management data, and these are stored into the 
auxiliary memory D1 per each of print jobs J1 through J5. 
When the print jobs J1 through J5 are stored into the auxiliary memory D1, 
the memory capacity of the auxiliary memory D1 at the moment is compared 
with the data amount of the print jobs J1 to J5 (in the step S603). If the 
memory capacity of the auxiliary memory D1 is larger, the print jobs are 
stored into the auxiliary memory D1, and the process goes to the step 
S605. On the contrary, if the memory capacity of the auxiliary memory D1 
is too low, the process goes to the step S604, where a warning that the 
memory capacity of the auxiliary memory D1 is low is made to the user who 
has generated the print jobs, and the generated print jobs are made 
invalid. 
In the step S605, the user who has generated print jobs goes to, for 
example, the printer P1 connected on the same network as the computer C1 
keeping the print jobs, and according to the contents displayed on the 
display 20 on the printer P1, the user selects the computer C1 by the 
mouse or so of the input device 22, and the process goes to the step S606. 
In the step S606, when the computer C1 is selected, the printer P1 inquires 
about all the print job management data kept in the selected computer C1 
via the communication network. At this moment, the print job management 
data to be transmitted on the communication network N are "Job ID", "Job 
Generator ID", "Job Event Date and Time", "Job Effective Term", "Job 
Retain Computer ID", "Job Ownership", "Job Reproduction Number", and 
"Print Content Index". At least "Password" should not be sent to the 
printer P1. 
Next, in the step S607, when the printer P1 receives the print job 
management data of the print jobs J1 to J5 except a password that the 
computer C1 keeps from the computer C1, the printer P1 displays a part of 
their contents on its display 20, and the process goes to the step S608. 
In the step S608, the user selects a desired print job (for example, print 
job J1) by use of the mouse or so of the input device 22 of the printer 
P1, and the process goes to the step S609. 
In the step S609, the printer P1 prompts the user to enter his or her 
password by displaying a message on its display 20, and the process goes 
to the next step S610. 
In the step S610, when user enters his or her password from the keyboard or 
so of the input device 22 of the printer P1, the password is sent via the 
communication network N to the computer C1 selected previously, and the 
process goes to the next step S611. 
In the step S611, the computer C1 compares the password sent from the 
printer P1 and the password of the owner of the selected print job J1, 
i.e., the user who has generated the job, and thereby judges whether the 
user who request print execution is the correct owner of the print job J1 
or not. 
If both the passwords are identical with each other, the process goes to 
the step S612, and the computer C1 immediately sends out the print content 
data of the print job J1 requested for printing to the printer P1 with 
receive request. The printer P1 receives the print content data of the 
print job J1, and executes printing accordingly. 
At the normal completion of print execution of the print job J1 in the 
printer P1, the notice to that effect is made from the printer P1 via the 
communication network N to the computer C1, and the process goes to the 
next step S613. In the step S613, the computer C1 subtracts "1" from the 
value of "Job Reproduction Number" of the print job management data of the 
print job J1, and the process goes to the next step S614. 
In the step S614, when the value of "Job Reproduction Number" is "0", the 
process goes to the step S615, and the print job J1 is regarded to be 
completed, and is deleted from the auxiliary memory D1 of the computer C1. 
On the other hand, when the value of "Job Reproduction Number" is not "0", 
the process goes to the step S616, and the print job J1 is kept in the 
auxiliary memory D1, and may be printed from either the printer P1 or P2 
until the "Effective Term" of the print job management data passes, or 
until the print job J1 is deleted by the generator of the print job J1. 
In this manner, the print job J1 may be accessed and printed from either 
the printer P1 or P2 on the communication network N to which the computer 
C1 keeping the print job J1 is connected; thereby, user's print waiting 
time is reduced. 
What is explained in reference to FIG. 6 is also effective in the case 
where there are plural users on the network N, who generates print jobs 
respectively, and execute printing from optional printers on the network 
N. In this case, a password is used to confirm whether the owner of a 
certain print job corresponds to the print executor or not, so even if the 
printers P1 and P2 are shared by plural users, the function to keep 
secrecy of printed matters is improved more than that in the conventional 
network print systems. And further, confusion in the network is avoided by 
not sending all the contents of print job at one time but sending only the 
print job management data. 
Then, in reference to FIG. 7 and FIG. 8, other operation processes in the 
network print system in FIG. 1 by the print job management program are 
explained hereinafter. Herein, explanation is made about the case where 
the ownership of a print job is given to other plural users than the 
generator of the print job. 
FIG. 7 is a flow chart to explain the operation processes by print job 
management program in the case where the ownership of a print job is given 
to other plural users. FIG. 8 is a schematic diagram to explain the data 
flow in the network print system in correspondence to the flow chart in 
FIG. 7. 
In FIG. 7, in the step S701, the user 1 generates print job J1 by the 
computer C1 (arrow (1) in FIG. 8). 
In the step S702, the generated print job J1 is stored into the auxiliary 
memory D1 of the computer C1 (arrow (2) in FIG. 8). That is, when a 
document or so is created for the purpose of being printed, it is stored 
into the auxiliary memory D1 as the print content data of print job J1. At 
the same time, the prescribed print job management data is also stored 
into the auxiliary memory D1. 
Then, the processes of the steps S603 through S604 in FIG. 6 are carried 
out, and the process goes to the step S703 in FIG. 7. 
Now here, it is supposed that the user 1 has to deliver the printed matter 
that is printed on the basis of the print job 1 to the users 2 and 3. 
In this case, the user 1, at the step S703, gives its job ownership to the 
users 2 and 3 by use of the print job management program (arrow (3) in 
FIG. 8). Namely, the user 1 enters the respective IDs and a common 
password of the users 2 and 3 from the input device such as a keyboard or 
so of the computer C1, and adds them to "Job Ownership" and "Password" of 
the print job management data of the print job J1. The users 2 and 3 may 
use the common password. That is, the common password is given to the user 
2 and 3 who execute common project. As a result, "Job Reproduction Number" 
of the print job management data of the print job J1 is also updated. 
Here, job ownership is given to the users 1, 2 and 3; therefore, "Job 
Reproduction Number" becomes "3". 
At this moment, the print job J1 is owned by the users 1, 2 and 3. Namely, 
the users 2 and 3 as well as user 1 may execute printing of the print job 
J1 from optional printers (printer P1 and printer P2) on the network N in 
the same manner mentioned already. 
Next, the process goes to the step S704, the user 1 gives the ownership of 
the users 2 and 3 to the print job j1, and the print job management 
program informs that the ownership of print job J1 has been changed to the 
users 2 and 3 (arrow (4) in FIG. 8). 
This notification may be made by another method, such as by e-mail. 
When the users 2 and 3 acknowledge the event of the print job J1 addressed 
to them by the above notification received by the computers C2 and C3 
respectively, then the process goes to the step S705. 
The processing operation in the step S705 are the same as the explanation 
in the steps S605 through S616 in FIG. 6. Namely, each of the users 1, 2 
and 3 accesses from an optional printer on the network (either of printer 
P1 or P2) to the computers C1 keeping the print job J1, collates the 
password, then executes printing operation (arrow (5) in FIG. 8). 
Namely, for example, when the user 2 executes printing operation, the user 
2 goes to the printer P1 in the step S605, and selects the computer C1 via 
the input device 22. In the step S606, the printer P1 inquires about all 
the print job management data kept in the selected computer C1 via the 
network N, and the process goes to the step S607, where the printer P1 
receives the print job management data of the print job kept by the 
computer C1 that is sent from the computer C1, and displays them on its 
display unit. Next, user 2 goes to the step S608, where user 2 selects the 
print job J1 from the printer P1, and in the step S609, the printer P1 
prompts the user 2 to enter the password. 
And in the step S610, when the user 2 enters the password from the keyboard 
or so of the input device 22 of the printer P1, the password is sent to 
the computer C1 selected previously, and the process goes to the next step 
S611. In the step S611, the printer C1 compares the password sent from the 
printer P1 and the password stored as the print job management data of the 
selected print job J1, and thereby judges whether the user 2 who requests 
print execution is the correct owner of the print job J1 or not. If both 
the passwords are identical with each other, the process goes to the step 
S612, and the computer C1 immediately sends out the print content data of 
the print job J1 requested for printing to the printer P1 with receive 
request. And the printer P1 receives the print content data of the print 
job J1, and executes printing operation accordingly. 
As mention previously, when the user 1 generates the print job J1, "Job 
Reproduction Number" shows "1", but when the user 1 gives the ownership of 
the print job J1 to the users 2 and 3, "Job Reproduction Number" of the 
print job J1 becomes "3". This number corresponds to the number of job 
owners. Here, it is supposed that the user 2 has executed printing of the 
print job J1 from the printer P1 in accordance with the above procedures. 
At the completion of print execution, the value of "Job Reproduction 
Number" is automatically subtracted, and becomes "2". In this case, the 
job reproduction number is not "0", therefore, the print job J1 is not 
regarded as to be completed. Further, when remaining users 1 and 3 carry 
out printing of the print job J1 in succession, the job reproduction 
number becomes "0", and the print job is completed, then the print job J1 
is deleted from the auxiliary memory D1 of the computer C1. 
In this manner mentioned above, under the control in accordance with the 
print job management program in the network print system of the present 
embodiment, the user 1 changes "Job Ownership" and "Password" of the print 
job management data about the print job J1 that has occurred in the 
computer C1. By this change, the ownership of the print job J1 is given 
also to plural users 2 and 3, and is stored in the auxiliary memory D1 of 
the computer C1. On the other hand, the print job management program gives 
notice of the occurrence of the print job J1 to the users 2 and 3, and the 
users 2 and 3 select the computer C1 from an optional printer (for 
example, the printer P1), and collate the password when they access the 
print job J1. By this collation, user 2 and user 3 judge that the user is 
the correct owner of the print job J1, then read the content data of the 
print job J1 from the auxiliary memory D1 of the computer C1. By sending 
the read content data to the printer P1 to execute printing operation, 
these plural users can keep the secrecy of printed matter and obtain 
printed matter of the identical content from an optional printer. And 
further, user's print waiting time may be reduced, and mistakes in 
printing may be eliminated. 
Also, the control of the reproduction number by "Job Reproduction Number" 
of the print job management data prevents inexhaustible print execution. 
Furthermore, when the "Job Effective Term" of the print job management data 
set for the occurred print job J1 passes, even if none of all the job 
owners (users 1, 2 and 3) is executing print operation, the print job J1 
is regarded to be stale, and the print job J1 is deleted from the 
auxiliary memory D1 of the computer C1. Thereby, the print job J1 that has 
become unnecessary without being referred to may be deleted easily from 
the auxiliary memory D1 therefore, memory capacity may be used 
efficiently. 
In the next place, in reference to FIGS. 9 and 10, other operation 
processes in the network print system in FIG. 1 by the print job 
management program are explained hereinafter. Herein, explanation is made 
especially about the case where the print content index among the print 
job data to be stored in auxiliary memory as shown in FIG. 2 may be 
optionally displayed to a user through the display 20 arranged at a 
printer. 
FIG. 9 is a flow chart showing operation processes by the print job 
management data in the case where a user may select one job whether to 
print out data directly, or to see only print content, or see the print 
content data and print it out. FIG. 10A to FIG. 10F show the transitions 
of the display contents illustrating the contents displayed on the screen 
of the display 20 almost in correspondence to the flow chart in FIG. 9. 
As shown in FIG. 9, the program to control printer on the network N is 
stored in ROM 14 (FIG. 4). After the system is turned on or reset, this 
program is transferred to RAM 16 (FIG. 4) and runs (step S901). When a 
user who has generated a print job on the network N or a user who is given 
ownership comes to, for example, the printer P2 on the network N, the 
display 20 of the printer P2 displays that the computers connected to the 
printer P2 via the network N are C1, C2, and C3 as shown in FIG. 10A (step 
S902). The user selects, for example, the computer C1 out of the computers 
C1, C2, and C3 via the input device 22 (step S903). 
When the computer C1 on the network N is selected by the user, the printer 
P2 outputs a request signal requesting the computer C1 to transmit the 
print job management data stored in the auxiliary memory D1 to the printer 
P2 (step S904). The print job management program of the computer C1, which 
receives the request signal, transmits the print job management data of 
all the print jobs that the computer C1 holds to the printer P2 via the 
network N. The display 20 of the printer P2 which has received the print 
job management data, as shown in FIG. 10B, displays, for example, job IDs, 
job generator IDs and job occurrence date and time among the print job 
management data in the form of a list (step S905). 
Then, the user selects desired print job via the input device 22 (step 
S906). Herein, the user may select whether to "PRINT" or to see the "PRINT 
CONTENT INDEX" as shown in FIG. 10C. 
If the user selects "PRINT CONTENT INDEX" ("CONTENT INDEX" in step S907), 
the printer P2 displays a screen to prompt the user to input his password 
on the display 20 as shown in FIG. 10D. The user inputs his or her 
password by use of keyboard of the input device 22 (step S908). The input 
password is transmitted to the computer C1 which holds the print job, and 
is collated with the password stored in the computer C1 by this computer 
C1. In the case where the result of the above collation is correct ("TRUE" 
in step S909), then the display 20 of the printer P2 displays the print 
content index of the selected print job as shown in FIG. 10E (step S910). 
The user may know the details of the print content obtained by the print 
job management data by looking at this print content index. 
In the collation of the step S909, in the case where the result of the 
collation is not correct, then the display 20 displays "ERROR" indication 
(step S911), and the processing returns to step S905. 
To the user who has seen the print content index in step S910, the display 
20 further displays a question whether to print it or not (step S912). If 
the user does not select "PRINT", then the processing returns to step 
S905. If the user selects "PRINT", a print format setting screen is 
displayed on the display 20. The user sets a print format via the input 
device 22 (step S913). Namely, for example, the user may scale down an 
image data of size A4 into an image data of size A5, and edit that image 
data so as to print two images scaled down on a paper sheet of size A4. Or 
the user may rotate an image to be printed out too. This is made by 
presetting the data format to be stored in the page memory 28 (FIG. 4). 
And then, when the user instructs the printer P2 to start printing 
operation through the input device 22, the printer P2 transmits to the 
computer C1 a signal requesting the computer C1 to transmit the print 
content data to the printer P2 (step S914). In response to this request 
signal, the computer C1 transmits the print content data and the printer 
P2 receives that data (step S915). The received print content data is 
stored into the page memory 28 in accordance with the format set in the 
step S913. On the basis of this stored data, the content data is printed 
on paper sheet (step S916). 
In the step S907, when the user selects "PRINT" ("TO PRINT" in the step 
S907), the printer P2 displays a screen prompting the user to input his or 
her password on the display 20 as shown in FIG. 10F. The user inputs his 
or her password through the keyboard of the input device 22, and the 
printer P2 transmits to the computer C1 that holds the print job the 
entered password and a signal requesting the computer C1 to transmit the 
print content data to the printer P2 (step S917). 
The password that has been transmitted to the computer C1 that holds the 
print job is collated with the password that has been stored in the 
computer C1 (step S918). In the collation of the step S918, in the case 
where the result of the collation is not correct, then the display 20 
displays "ERROR" indication (step S911), and the processing returns to 
step S905. 
In the case where the result of the above collation is correct, a screen to 
prompt the user to set a format is displayed on the display 20. When the 
user sets a format as previously described in the step S913 and instructs 
the input device 22 to start printing operation, the printer P2 receives 
the print content data transmitted from the computer C1 in response to the 
request signal in the step S917 (step S920). The received print content 
data is stored in the page memory 28 in accordance with the format set in 
the step S919. On the basis of this stored data, the content data is 
printed out on paper sheet (step S916). 
In this manner, only a specified user authorized by password collation can 
see the print content index. Thereby, private printed contents and top 
secret documents can be kept secret. And further, user can first see the 
print content index and then judge whether to print it or not. 
In a network print system according to the present invention, print job has 
job ownership and job reproduction right. The job ownership may be given 
to other person than a print job generator too. And the job reproduction 
right increases in accordance with the number of job owners. 
In the present invention, this job ownership may be given to the user 
itself in plural. In this case, the user does so to obtain plural copies 
of an identical printed matter. Namely, a certain print job generator may 
give another job ownership to himself or herself, and in this case, two 
people own an identical print job though the job owners are identical; 
therefore, job reproduction right increases to 2 (two). 
In this way, this user may obtain plural copies of printed matter from the 
network print system. 
Also, when a printed matter is being output by a printer on the same 
network, and the same printed matter is to be output by another free 
printer on the same network, the management of copy number is made by the 
print job management program on the basis of the number of job 
reproduction right. Therefore, while job reproduction right is not 0 
(zero), it has no problem to print and output print job by any printer on 
the same network, and also to print and output an identical print job from 
plural printers at the same time. 
As shown in FIG. 11, for example, the user 1 may give to the user 1 itself 
further two reproduction rights of print job J1 as print jobs J2 and J3 in 
order to output 100 sheets of printed matter. Thereby, the user 1 may 
obtain 3 copies of 100 sheets of printed matter. That is, the user 1 may 
execute print job J1 by use of the printer P1, print job J2 by the printer 
P2, and print job j3 by the printer P3 respectively. The user 1 selects 
print job J1 at the printer P1, print job J2 at the printer P2, and print 
job J3 at the printer P3, and outputs 100 sheets of printed matter 
respectively by the printers P1, P2 and P3 almost at the same time in the 
same procedures as mentioned previously. Thereby, plural copies of many 
sheets of printed matter may be output efficiently in a shorter time. 
Output is available of course by a single unit of printer, however, in 
this case output must be made in a series of part 1, part 2, and part 3; 
therefore, it will take much time to output plural copies of many sheets 
of printed matter. But, as described above, the provision of print job 
reproduction right to a single user enables to output them at the same 
time by use of plural units of printer. Accordingly, it is available to 
output plural copies of many sheets of printed matter in a shorter time; 
therefore, operation is made far more effective. 
As explained above, in accordance with the present invention, user's print 
waiting time is reduced, mistakes in printing are eliminated, and the 
secrecy function of printed matter is improved. Further, the present 
invention enables to provide a network print system where specified plural 
users can obtain printed matters with identical contents from optional 
printers. 
The invention may be embodied in other specific forms without departing 
from the spirit or essential characteristics thereof. The present 
embodiments are therefore to be considered in all respects as illustrative 
and not restrictive, the scope of the invention being indicated by the 
appended claims rather than by the foregoing description and all changes 
which come within the meaning and range of equivalency of the claims are 
therefore intended to be embraced therein.