US5675725A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Computer backup system operable with open files
Assignee: CA Inc
•
Filing: 1995-06-06
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Granted: 1997-10-07
•
Expires: 2015-06-06
Abstract
Abstract A backup program for a computer system with a hard disk maintains a record of changes made to the data in a file being backed up. During backup both the original and update file portions or records are stored, and the backup program reads the original data while other applications read the updated data. To identify whether a read operation is initiated by the backup program or by another application, the system determines, using the stack, the source of the read request. Alternatively it interrogates the user, process or task id. Access to the file by the backup program is guaranteed by manipulating the System File Table. It is ensured that the file is in a `good` state by delaying the start of the backup operation for a predetermined period.
Inventors
- 👤 Peter B. Malcolm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:25
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/14; G06F9/00; G06F9/06; G06F9/46; G06F9/52; G06F11/1446; G06F11/1458; G06F11/1466
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
353 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means; the method comprising the steps of: providing a backup process, running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed; providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means, said backup process being capable of operating with files which are open to access by said instructions; providing file opening means for opening a file to be read by a normal read operation and having a denying function for denying access to said file by other read operations; disabling said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation; maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and wherein the step of determining whether the read instruction relates to a backup read operation or a normal read operation comprises the step of looking at the area of memory from which said read instruction originates to determine the identity of the program which initiated said read instruction.
Claim 2
Independent Claim
353 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means; the method comprising the steps of: providing a backup process, running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed; providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means, said backup process being capable of operating with files which are open to access by said instructions; providing file opening means for opening a file to be read by a normal read operation and having a denying function for denying access to said file by other read operations; disabling said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation; maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and wherein the step of determining whether the read instruction relates to a backup read operation or a normal read operation comprises the step of looking at the area of memory from which said read instruction originates to determine the identity of the program which initiated said read instruction.
Claim 3
Independent Claim
359 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, in a computer network; the method comprising the steps of: providing a backup process, running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed; providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means, said backup process being capable of operating with files which are open to access by said instructions; providing file opening means for opening a file to be read by a normal read operation and having a denying function for denying access to said file by other read operations; disabling said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation; maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and allocating to said backup process a user, process or task identification, said step of determining whether said read instruction relates to a backup read operation or a normal read operation comprising determining whether said read operation is requested by a user or program with said user, process or task identification.
Claim 4
Independent Claim
359 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, in a computer network; the method comprising the steps of: providing a backup process, running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed; providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means, said backup process being capable of operating with files which are open to access by said instructions; providing file opening means for opening a file to be read by a normal read operation and having a denying function for denying access to said file by other read operations; disabling said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation; maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and allocating to said backup process a user, process or task identification, said step of determining whether said read instruction relates to a backup read operation or a normal read operation comprising determining whether said read operation is requested by a user or program with said user, process or task identification.
Claim 5
Independent Claim
255 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, the method comprising the steps of: providing a backup process, running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; and determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; wherein the step of determining whether said read instruction relates to a backup read operation or a normal read operation comprises the step of looking at the area of memory from which said read instruction originates to determine the identity of the program which initiated said read instruction.
Claim 6
Independent Claim
255 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, the method comprising the steps of: providing a backup process, running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; and determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; wherein the step of determining whether said read instruction relates to a backup read operation or a normal read operation comprises the step of looking at the area of memory from which said read instruction originates to determine the identity of the program which initiated said read instruction.
Claim 7
Dependent Claim
27 words
A method as claimed in claim 3, in which said looking step comprises interrogating a stack to determine locations stored on the stack and interrogating said locations.
Claim 8
Dependent Claim
25 words
A method as claimed in claim 4, in which said looking step comprises comparing code around said locations with code expected from the backup program.
Claim 9
Dependent Claim
38 words
A method as claimed in claim 4, in which said looking step comprises determining a Program Segment Prefix and an Environment String associated with the program at said locations, and determining the program name using said Environment String.
Claim 10
Independent Claim
267 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, in a computer network; the method comprising the steps of: providing a backup process, running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; and determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and wherein the improvement comprises allocating to said backup process a user, process or task identification, whereby said step of determining whether the read instruction relates to a backup read operation or a normal read operation comprises determining whether said read operation is requested by a user or program with said user, process or task identification.
Claim 11
Independent Claim
267 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, in a computer network; the method comprising the steps of: providing a backup process, running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; and determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and wherein the improvement comprises allocating to said backup process a user, process or task identification, whereby said step of determining whether the read instruction relates to a backup read operation or a normal read operation comprises determining whether said read operation is requested by a user or program with said user, process or task identification.
Claim 12
Independent Claim
163 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, said method comprising the steps of: providing a backup process, running on the computer system, which is operable to issue a start signal and a stop signal and to perform at lest one backup read operation to read original data from said storage means; and providing instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; and providing file opening means for opening a file to be read by a normal read operation and denying access to said file by other read operations; wherein the improvement comprises providing means associated with said backup process which disables said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation.
Claim 13
Independent Claim
163 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, said method comprising the steps of: providing a backup process, running on the computer system, which is operable to issue a start signal and a stop signal and to perform at lest one backup read operation to read original data from said storage means; and providing instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; and providing file opening means for opening a file to be read by a normal read operation and denying access to said file by other read operations; wherein the improvement comprises providing means associated with said backup process which disables said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation.
Claim 14
Dependent Claim
32 words
A method as claimed in claim 8, in which said computer system maintains a table of open files, and in which the denying function is disabled by temporarily reversibly altering the table.
Claim 15
Independent Claim
147 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, the method comprising the steps of: providing a backup process, running on said computer system, which is operable to issue a start signal and a stop signal and to perform at least one backup read operation to read original data from said storage means; and providing instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal write operation to write data to said storage means; and in which said backup process is capable of operating with files which are open to access by said instructions, wherein the improvement comprises the step of delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed.
Claim 16
Independent Claim
147 words
A method of operating a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, the method comprising the steps of: providing a backup process, running on said computer system, which is operable to issue a start signal and a stop signal and to perform at least one backup read operation to read original data from said storage means; and providing instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal write operation to write data to said storage means; and in which said backup process is capable of operating with files which are open to access by said instructions, wherein the improvement comprises the step of delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed.
Claim 17
Dependent Claim
356 words
In a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means; a backup system comprising: a backup program, for running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; means for delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed; means for providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means, said backup program being capable of operating with files which are open to access by said instructions; file opening means for opening a file to be read by a normal read operation and having a denying function for denying access to said file by other read operations; means for disabling said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation; means for maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; means for determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and wherein the means for determining whether the read instruction relates to a backup read operation or a normal read operation comprises means for looking at the area of memory from which said read instruction originates to determine the identity of the program which initiated said read instruction.
Claim 18
Dependent Claim
356 words
In a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means; a backup system comprising: a backup program, for running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; means for delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed; means for providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means, said backup program being capable of operating with files which are open to access by said instructions; file opening means for opening a file to be read by a normal read operation and having a denying function for denying access to said file by other read operations; means for disabling said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation; means for maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; means for determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and wherein the means for determining whether the read instruction relates to a backup read operation or a normal read operation comprises means for looking at the area of memory from which said read instruction originates to determine the identity of the program which initiated said read instruction.
Claim 19
Dependent Claim
367 words
In a computer network, a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means; the microprocessor-based computer system comprising: a backup program, for running on said computer system, which is operable to issue a start signal and a stop signal and to issue an least one backup read instruction to read original data from said storage means; means for delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed; means for providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means, said backup program being capable of operating with files which are open to access by said instructions; file opening means for opening a file to be read by a normal read operation and having a denying function for denying access to said file by other read operations; means for disabling said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation; means for maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; means for determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and means for allocating to said backup program a user, process or task identification, said means for determining whether said read instruction relates to a backup read operation or a normal read operation comprising means for determining whether said read operation is requested by a user or program with said user, process or task identification.
Claim 20
Dependent Claim
367 words
In a computer network, a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means; the microprocessor-based computer system comprising: a backup program, for running on said computer system, which is operable to issue a start signal and a stop signal and to issue an least one backup read instruction to read original data from said storage means; means for delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed; means for providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means, said backup program being capable of operating with files which are open to access by said instructions; file opening means for opening a file to be read by a normal read operation and having a denying function for denying access to said file by other read operations; means for disabling said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation; means for maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; means for determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and means for allocating to said backup program a user, process or task identification, said means for determining whether said read instruction relates to a backup read operation or a normal read operation comprising means for determining whether said read operation is requested by a user or program with said user, process or task identification.
Claim 21
Dependent Claim
255 words
In a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, a backup system comprising: a backup program, for running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; means for providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; means for maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; and means for determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; wherein the means for determining whether said read instruction relates to a backup read operation or a normal read operation comprises means for looking at the area of memory from which said read instruction originates to determine the identity of the program which initiated said read instruction.
Claim 22
Dependent Claim
255 words
In a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, a backup system comprising: a backup program, for running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; means for providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; means for maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; and means for determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; wherein the means for determining whether said read instruction relates to a backup read operation or a normal read operation comprises means for looking at the area of memory from which said read instruction originates to determine the identity of the program which initiated said read instruction.
Claim 23
Dependent Claim
29 words
A system as claimed in claim 13, in which said looking means comprises means for interrogating a stack to determine locations stored on the stack and interrogating said locations.
Claim 24
Dependent Claim
27 words
A system as claimed in claim 14, in which said looking means comprises means for comparing code around said locations with code expected from the backup program.
Claim 25
Dependent Claim
40 words
A system as claimed in claim 14, in which said looking means comprises means for determining a Program Segment Prefix and an Environment String associated with the program at said locations, and determining the program name using said Environment String.
Claim 26
Dependent Claim
272 words
In a computer network, a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means; the microprocessor-based computer system comprising: a backup program, for running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; means for providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; means for maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; and means for determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and wherein the improvement comprises means for allocating to said backup program a user, process or task identification, whereby said means for determining whether the read instruction relates to a backup read operation or a normal read operation comprises means for determining whether said read operation is requested by a user or program with said user, process or task identification.
Claim 27
Dependent Claim
272 words
In a computer network, a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means; the microprocessor-based computer system comprising: a backup program, for running on said computer system, which is operable to issue a start signal and a stop signal and to issue at least one backup read instruction to read original data from said storage means; means for providing first instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; means for maintaining a record of data written to said storage means, to relate corresponding areas in a primary storage area of said storage means and a secondary storage area of said storage means; and means for determining, after receiving said start signal and on receiving a read instruction, whether said read instruction relates to a backup read operation or a normal read operation, and on performing one of said backup and normal read operations, interrogating said record to read data from one of said primary and said secondary storage areas according to said record, and on performing the other of said backup and normal read operations, reading data from said primary storage area; and wherein the improvement comprises means for allocating to said backup program a user, process or task identification, whereby said means for determining whether the read instruction relates to a backup read operation or a normal read operation comprises means for determining whether said read operation is requested by a user or program with said user, process or task identification.
Claim 28
Dependent Claim
158 words
In a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, a backup system comprising: a backup program, for running on the computer system, which is operable to issue a start signal and a stop signal and to perform at lest one backup read operation to read original data from said storage means; and means for providing instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; and file opening means for opening a file to be read by a normal read operation and denying access to said file by other read operations; wherein the improvement comprises means associated with said backup program for disabling said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation.
Claim 29
Dependent Claim
158 words
In a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, a backup system comprising: a backup program, for running on the computer system, which is operable to issue a start signal and a stop signal and to perform at lest one backup read operation to read original data from said storage means; and means for providing instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal read operation to read data from said storage means; and file opening means for opening a file to be read by a normal read operation and denying access to said file by other read operations; wherein the improvement comprises means associated with said backup program for disabling said denying function of said file opening means to permit simultaneous read access to said file by a backup read operation and a normal read operation.
Claim 30
Dependent Claim
32 words
A system as claimed in claim 18, in which said computer system maintains a table of open files, and in which the denying function is disabled by temporarily reversibly altering the table.
Claim 31
Dependent Claim
143 words
In a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, a backup system comprising: a backup program, for running on said computer system, which is operable to issue a start signal and a stop signal and to perform at least one backup read operation to read original data from said storage means; and means for providing instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal write operation to write data to said storage means; and in which said backup program is capable of operating with files which are open to access by said instructions, wherein the improvement comprises means for delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed.
Claim 32
Dependent Claim
143 words
In a microprocessor-based computer system including an instruction memory, a central processing unit and a storage means, a backup system comprising: a backup program, for running on said computer system, which is operable to issue a start signal and a stop signal and to perform at least one backup read operation to read original data from said storage means; and means for providing instructions stored in said memory to said central processing unit to cause said central processing unit to perform at least one normal write operation to write data to said storage means; and in which said backup program is capable of operating with files which are open to access by said instructions, wherein the improvement comprises means for delaying the issue of a start signal until any series of write operations to a file to be backed up have been completed.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-10-06 | 2001-04-07 | 2001-10-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-10-06 | 2005-04-07 | 2005-10-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-10-06 | 2009-04-07 | 2009-10-07 | $7700.00 | Window Closed / Lapsed |