초록 ▼

A method of and system for control of access to add an event notification as a log record in a computer system. Each potential log record is associated with one or more logs, each of which has one or more log owners. Grant of access to add a log record to the information in a particular log is restr

A method of and system for control of access to add an event notification as a log record in a computer system. Each potential log record is associated with one or more logs, each of which has one or more log owners. Grant of access to add a log record to the information in a particular log is restricted to the owner(s) of that log. A list of owners of a log can be changed from time to time, based upon present circumstances or the presence of special conditions.

대표청구항 ▼

A method of and system for control of access to add an event notification as a log record in a computer system. Each potential log record is associated with one or more logs, each of which has one or more log owners. Grant of access to add a log record to the information in a particular log is restr

A method of and system for control of access to add an event notification as a log record in a computer system. Each potential log record is associated with one or more logs, each of which has one or more log owners. Grant of access to add a log record to the information in a particular log is restricted to the owner(s) of that log. A list of owners of a log can be changed from time to time, based upon present circumstances or the presence of special conditions. of unique tokens, whereby an updated data file can be created from the initial data file and the thus created merge structure. 4. A method as claimed in claim 1, wherein each reuse token comprises a reuse token indicator, an offset value identifying the position of bytes in another delta file or the base file and a number value representing the number of bytes associated with the position identified by the offset value. 5. A method as claimed in claim 1, wherein each unique token comprises a unique token indicator, a file identifier for identifying the file containing unique data for the thus created merge structure, an offset value identifying the position of bytes in another delta file or the base file and a number value representing the number of bytes associated with the position identified by the offset value. 6. A method as claimed in claim 1, further comprising: defining for each token in the further merge structure a window of locations in the initial merge structure from data associated with the token in the further merge structure; identifying for each window in the initial merge structure the or each token in the further merge structure that refers to data in the window; and replacing thus identified tokens in the further merge structure with data derived from tokens in the window of the initial merge structure. 7. A method as claimed in claim 1, further comprising: identifying reuse tokens in a merge structure; appending in the merge structure the unique token or tokens to which the reuse token pertains; and replacing the reuse token with an offset token which comprises a pointer that identifies the position at which the unique token or tokens are appended in the merge structure. 8. A method as claimed in claim 7, wherein the unique token or tokens are appended at the end of the merge structure. 9. A method as claimed in claim 1, further comprising: for each delta file identifying reuse tokens therein; and for each identified reuse token modifying the token, tokens or token portions in the preceding delta file to which the reuse token pertains by replacing the same with a forward reuse token which identifies the reuse token in the delta file, thereby to create bi-directional delta files. 10. A method as claimed in claim 9, further comprising, when an identified reuse token in the delta file pertains to a portion of one or more tokens in the preceding delta file, modifying the remaining portion of the one or more tokens to which the reuse token does not pertain. 11. A method as claimed in claim 1, further comprising reviewing tokens in the created merge structure to identify as redundant those delta files to which no reference is made. 12. A method as claimed in claim 11, further comprising deleting redundant delta files. 13. A method as claimed in claim 1, further comprising saving the created merge structure. 14. A method as claimed in claim 1, further comprising using the created merge structure to create the updated file from the base file. 15. A method of creating a current file from an initial file and a set of difference files that defines a sequence of changes between the initial file and the current file, the method comprising: merging the difference files according to the method as claimed in claim 1 so as to remove redundant information therefrom and thus create a changes file representing all changes to be applied to the initial file in order to arrive at the current file; and modifying the initial file using the information in the changes file. 16. A method as claimed in claim 15, wherein each difference file comprises one or more sets of information each defining changes in a block of data at a position in an earlier difference file or in the initial file, and the initial file is modified by effecting the changes defined by the sets of information. 17. A method as claimed in claim 16, wherein one or more of the sets of information includes information which identifies the loca