1XBase::Base(3) User Contributed Perl Documentation XBase::Base(3)
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6 XBase::Base - Base input output module for XBase suite
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9 Used indirectly, via XBase or XBase::Memo.
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12 This module provides catch-all I/O methods for other XBase classes,
13 should be used by people creating additional XBase classes/methods.
14 There is nothing interesting in here for users of the XBase(3) module.
15 Methods in XBase::Base return nothing (undef) on error and the error
16 message can be retrieved using the errstr method.
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18 Methods are:
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20 new Constructor. Creates the object and if the file name is specified,
21 opens the file.
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23 open
24 Opens the file and using method read_header reads the header and
25 sets the object's data structure. The read_header should be defined
26 in the derived class, there is no default.
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28 close
29 Closes the file, doesn't destroy the object.
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31 drop
32 Unlinks the file.
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34 create_file
35 Creates file of given name. Second (optional) paramater is the
36 permission specification for the file.
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38 The reading/writing methods assume that the file has got header of
39 length header_len bytes (possibly 0) and then records of length
40 record_len. These two values should be set by the read_header method.
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42 seek_to, seek_to_record
43 Seeks to absolute position or to the start of the record.
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45 read_record, read_from
46 Reads data from specified position (offset) or from the given
47 record. The second parameter (optional for read_record) is the
48 length to read. It can be negative, and at that case the read will
49 not complain if the file is shorter than requested.
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51 write_to, write_record
52 Writes data to the absolute position or to specified record
53 position. The data is not padded to record_len, just written out.
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55 General locking methods are locksh, lockex and unlock, they call
56 _locksh, _lockex and _unlock which can be redefined to allow any way
57 for locking (not only the default flock). The user is responsible for
58 calling the lock if he needs it.
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60 No more description -- check the source code if you need to know more.
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63 0.129
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66 (c) 1997--1999 Jan Pazdziora, adelton@fi.muni.cz
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69 perl(1), XBase(3)
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73perl v5.12.0 2001-08-19 XBase::Base(3)