UDataInfo Struct Reference

UDataInfo contains the properties about the requested data. More...

#include <udata.h>

Data Fields

uint16_t size
 sizeof(UDataInfo)
uint16_t reservedWord
 unused, set to 0
uint8_t isBigEndian
 0 for little-endian machine, 1 for big-endian
uint8_t charsetFamily
 see U_CHARSET_FAMILY values in utypes.h
uint8_t sizeofUChar
 sizeof(UChar), one of { 1, 2, 4 }
uint8_t reservedByte
 unused, set to 0
uint8_t dataFormat [4]
 data format identifier
uint8_t formatVersion [4]
 versions: [0] major [1] minor [2] milli [3] micro
uint8_t dataVersion [4]
 versions: [0] major [1] minor [2] milli [3] micro

Detailed Description

UDataInfo contains the properties about the requested data.

This is meta data.

This structure may grow in the future, indicated by the size field.

The platform data property fields help determine if a data file can be efficiently used on a given machine. The particular fields are of importance only if the data is affected by the properties - if there is integer data with word sizes > 1 byte, char* text, or UChar* text.

The implementation for the udata_open[Choice]() functions may reject data based on the value in isBigEndian. No other field is used by the udata API implementation.

The dataFormat may be used to identify the kind of data, e.g. a converter table.

The formatVersion field should be used to make sure that the format can be interpreted. I may be a good idea to check only for the one or two highest of the version elements to allow the data memory to get more or somewhat rearranged contents, for as long as the using code can still interpret the older contents.

The dataVersion field is intended to be a common place to store the source version of the data; for data from the Unicode character database, this could reflect the Unicode version.

Stable:
ICU 2.0

Definition at line 106 of file udata.h.


Field Documentation

see U_CHARSET_FAMILY values in utypes.h

Stable:
ICU 2.0

Definition at line 122 of file udata.h.

data format identifier

Stable:
ICU 2.0

Definition at line 134 of file udata.h.

versions: [0] major [1] minor [2] milli [3] micro

Stable:
ICU 2.0

Definition at line 142 of file udata.h.

versions: [0] major [1] minor [2] milli [3] micro

Stable:
ICU 2.0

Definition at line 138 of file udata.h.

0 for little-endian machine, 1 for big-endian

Stable:
ICU 2.0

Definition at line 118 of file udata.h.

unused, set to 0

Stable:
ICU 2.0

Definition at line 130 of file udata.h.

unused, set to 0

Stable:
ICU 2.0

Definition at line 113 of file udata.h.

uint16_t UDataInfo::size

sizeof(UDataInfo)

Stable:
ICU 2.0

Definition at line 109 of file udata.h.

sizeof(UChar), one of { 1, 2, 4 }

Stable:
ICU 2.0

Definition at line 126 of file udata.h.


The documentation for this struct was generated from the following file:
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Generated on Sat Jan 23 15:17:45 2010 for ICU 4.3.4 by  doxygen 1.6.1