US5572709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Using dynamically-linked libraries to add side effects to operations
Assignee: Alcatel Lucent SAS
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Filing: 1993-06-18
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Granted: 1996-11-05
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Expires: 2013-06-18
Abstract
Abstract A backup file system which can be used without modification of application programs, the operating system, or the hardware. The backup file system is implemented by means of a dynamically-linkable replacement library and user-level processes on a primary computer system and a backup computer system. The dynamically-linkable replacement library has the same interfaces as a standard dynamically-linkable library of file operations. The functions in the replacement library perform the same file operations as their counterparts in the standard library; in addition, they send messages specifying the just-performed operation to a user-level process on the backup computer system. The user-level process executes the operation specified in the message on a backup file in the backup computer system. The files to be backed up are specified by identifying subtrees in the namespace of the primary file system; the subtrees make up a user-defined namespace. The backup file system is made fault tolerant by the use of monitor processes which monitor the backup computer system and the processes of the backup file system and deal with failures as required to keep the backup file system operating.
Inventors
- 👤 Glenn S. Fowler
- 👤 Yennun Huang
- 👤 David G. Korn
- 👤 Chung-Hwa H. Rao
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:35
CPC Classifications
G; G06; G06F; G06F11/00; G06F11/07; G06F11/16; G06F11/20; G06F11/2053; G06F11/2056; G06F11/2071; G06F16/00; G06F16/10; G06F9/00; G06F9/06; G06F9/46; G06F9/52
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
107 words
Apparatus for selectively adding a side effect to an operation which is performed by executing a function in a dynamically-linked library, the apparatus comprising: means for associating an indication that the side effect is to be added with the operation; and a dynamically-linked replacement library which replaces the dynamically-linked library and contains a replacement function, the replacement function performing the operation in the same manner as the function in the dynamically-linked library and further determining from the means for associating the indication whether the side effect is to be performed for the operation and performing the side effect when the means for associating the indication so indicates.
Claim 2
Dependent Claim
107 words
Apparatus for selectively adding a side effect to an operation which is performed by executing a function in a dynamically-linked library, the apparatus comprising: means for associating an indication that the side effect is to be added with the operation; and a dynamically-linked replacement library which replaces the dynamically-linked library and contains a replacement function, the replacement function performing the operation in the same manner as the function in the dynamically-linked library and further determining from the means for associating the indication whether the side effect is to be performed for the operation and performing the side effect when the means for associating the indication so indicates.
Claim 3
Dependent Claim
95 words
A file replication system comprising: means for executing an application program which operates on a first file using a function from a first dynamically-linked library; a second dynamically-linked library which replaces the first dynamically-linked library and contains a replacement function for the function from the first dynamically-linked library, the replacement function operating on the file in the same fashion as the function from the first library and further sending a message specifying another operation on another file which is substantially the same as the operation performed by executing the function from the first dynamically-linked library.
Claim 4
Dependent Claim
95 words
A file replication system comprising: means for executing an application program which operates on a first file using a function from a first dynamically-linked library; a second dynamically-linked library which replaces the first dynamically-linked library and contains a replacement function for the function from the first dynamically-linked library, the replacement function operating on the file in the same fashion as the function from the first library and further sending a message specifying another operation on another file which is substantially the same as the operation performed by executing the function from the first dynamically-linked library.
Claim 5
Dependent Claim
27 words
The apparatus set forth in claim 1 wherein: the operation is an operation on an entity; and the means for associating associates the indication with the entity.
Claim 6
Dependent Claim
18 words
The apparatus set forth in claim 3 wherein: the side effect is performing another operation on another entity.
Claim 7
Dependent Claim
51 words
The apparatus set forth in claim 4 wherein: the operation is performed in a first system; the other operation is performed in a second system; and the side effect sends a message to the second system specifying the other operation and the second system responds thereto by performing the other operation.
Claim 8
Dependent Claim
73 words
The apparatus set forth in claim 5 wherein: the means for associating associates the indication with the entity by associating the indication with an identifier for the entity; the apparatus further comprises means for mapping the identifier for the entity to an identifier for the other entity; and the message includes the identifier for the entity and the second system employs the means for mapping to obtain the identifier for the other entity.
Claim 9
Dependent Claim
46 words
The apparatus set forth in claim 6 wherein: when the function from the dynamically-lined library has an effect on the identifier for the entity, the side effect includes altering the means for associating and the means for mapping as required by the effect on the identifier.
Claim 10
Dependent Claim
19 words
The apparatus set forth in claim 6 wherein: the first system and the second system have separate name spaces.
Claim 11
Independent Claim
87 words
The apparatus set forth in any of claims 5, 6, 7, or 8 wherein: the operation is one of a sequence thereof; and the apparatus further comprises fault tolerant means for determining whether either the first system or the second system has failed and restarting the failed system; first means responsive to the fault tolerant means for recording the sequence of operations which occur during the failure; and second means responsive to the fault tolerant means for performing the recorded sequence when the failed system is restarted.
Claim 12
Independent Claim
21 words
The apparatus set forth in any of claims 3, 4, 5, 6, 7, or 8 wherein: the entity is a file.
Claim 13
Independent Claim
33 words
The apparatus set forth in any of claims 3, 4, 5, 6, or 8 wherein: the other operation is substantially the same as that performed by executing the function in the dynamically-linked library.
Claim 14
Independent Claim
26 words
The apparatus set forth in any of claims 3, 4, 5, 6, or 8 wherein: the side effect includes modifying the means for associating an indication.
Claim 15
Dependent Claim
57 words
A storage medium which is readable by a computer system in which an operation is performed by executing code in a dynamically linked library, the storage medium being characterized in that: the storage medium contains code which, when executed, implements the apparatus set forth in any of claims 1, 2, 3, 4, 5, 6, 7, or 8.
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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) | 1999-11-05 | 2000-05-06 | 2000-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-11-05 | 2004-05-06 | 2004-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-11-05 | 2008-05-06 | 2008-11-05 | $7700.00 | Window Closed / Lapsed |