ICU 78.2 78.2

Macros | Typedefs | Enumerations | Functions
utypes.h File Reference

Basic definitions for ICU, for both C and C++ APIs. More...

`#include "unicode/umachine.h"`
`#include "unicode/uversion.h"`
`#include "unicode/uconfig.h"`
`#include <float.h>`
`#include "unicode/utf.h"`

Go to the source code of this file.

## Macros
#define | U_ICUDATA_TYPE_LETTER "l"
| This is a platform-dependent string containing one letter: More...
#define | U_ICUDATA_TYPE_LITLETTER l
| The non-string form of U_ICUDATA_TYPE_LETTER. More...
#define | U_ICUDATA_NAME "icudt" U_ICU_VERSION_SHORT U_ICUDATA_TYPE_LETTER
| A single string literal containing the icudata stub name. More...
#define | U_ICUDATA_ENTRY_POINT U_DEF2_ICUDATA_ENTRY_POINT(U_ICU_VERSION_MAJOR_NUM,U_LIB_SUFFIX_C_NAME)
| U_ICU_ENTRY_POINT is the name of the DLL entry point to the ICU data library. More...
#define | NULL ((void *)0)
| Define NULL if necessary, to nullptr for C++ and to ((void *)0) for C. More...
#define | U_MILLIS_PER_SECOND (1000)
| The number of milliseconds per second. More...
#define | U_MILLIS_PER_MINUTE (60000)
| The number of milliseconds per minute. More...
#define | U_MILLIS_PER_HOUR (3600000)
| The number of milliseconds per hour. More...
#define | U_MILLIS_PER_DAY (86400000)
| The number of milliseconds per day. More...
#define | U_DATE_MAX DBL_MAX
| Maximum UDate value. More...
#define | U_DATE_MIN -U_DATE_MAX
| Minimum UDate value. More...
#define | U_COMBINED_IMPLEMENTATION 1
| Set to export library symbols from inside the ICU library when all of ICU is in a single library. More...
#define | U_DATA_API U_EXPORT
| Set to export library symbols from inside the stubdata library, and to import them from outside. More...
#define | U_COMMON_API U_EXPORT
| Set to export library symbols from inside the common library, and to import them from outside. More...
#define | U_I18N_API U_EXPORT
| Set to export library symbols from inside the i18n library, and to import them from outside. More...
#define | U_LAYOUT_API U_EXPORT
| Set to export library symbols from inside the layout engine library, and to import them from outside. More...
#define | U_LAYOUTEX_API U_EXPORT
| Set to export library symbols from inside the layout extensions library, and to import them from outside. More...
#define | U_IO_API U_EXPORT
| Set to export library symbols from inside the ustdio library, and to import them from outside. More...
#define | U_TOOLUTIL_API U_EXPORT
| Set to export library symbols from inside the toolutil library, and to import them from outside. More...
#define | U_DATA_API_CLASS U_DATA_API
| Set to export library symbols from inside the stubdata library, and to import them from outside, to be used on a class. More...
#define | U_COMMON_API_CLASS U_COMMON_API
| Set to export library symbols from inside the common library, and to import them from outside, to be used on a class. More...
#define | U_I18N_API_CLASS U_I18N_API
| Set to export library symbols from inside the i18n library, and to import them from outside, to be used on a class. More...
#define | U_LAYOUT_API_CLASS U_LAYOUT_API
| Set to export library symbols from inside the layout engine library, and to import them from outside, to be used on a class. More...
#define | U_LAYOUTEX_API_CLASS U_LAYOUTEX_API
| Set to export library symbols from inside the layout extensions library, and to import them from outside, to be used on a class. More...
#define | U_IO_API_CLASS U_IO_API
| Set to export library symbols from inside the ustdio library, and to import them from outside, to be used on a class. More...
#define | U_TOOLUTIL_API_CLASS U_TOOLUTIL_API
| Set to export library symbols from inside the toolutil library, and to import them from outside, to be used on a class. More...
#define | U_STANDARD_CPP_NAMESPACE
| Control of C++ Namespace. More...
#define | U_SUCCESS(x) ((x)<=U_ZERO_ERROR)
| Does the error code indicate success? More...
#define | U_FAILURE(x) ((x)>U_ZERO_ERROR)
| Does the error code indicate a failure? More...
#define | U_SHOW_CPLUSPLUS_API 0
| When defined to 1 (=default) and compiled with a C++ compiler, both C and C++ APIs are visible. More...
#define | U_SHOW_CPLUSPLUS_HEADER_API 0
| When defined to 1 (=default) and compiled with a C++ compiler, C++ header-only APIs are visible. More...
#define | U_HIDE_DRAFT_API 1
| Define this to 1 to request that draft API be "hidden". More...
#define | U_HIDE_INTERNAL_API 1
| Define this to 1 to request that internal API be "hidden". More...

## Typedefs
typedef double | UDate
| Date and Time data type. More...
typedef enum UErrorCode | UErrorCode
| Standard ICU4C error code type, a substitute for exceptions. More...

## Enumerations
enum | UErrorCode { U_USING_FALLBACK_WARNING = -128 , U_ERROR_WARNING_START = -128 , U_USING_DEFAULT_WARNING = -127 , U_SAFECLONE_ALLOCATED_WARNING = -126 , U_STATE_OLD_WARNING = -125 , U_STRING_NOT_TERMINATED_WARNING = -124 , U_SORT_KEY_TOO_SHORT_WARNING = -123 , U_AMBIGUOUS_ALIAS_WARNING = -122 , U_DIFFERENT_UCA_VERSION = -121 , U_PLUGIN_CHANGED_LEVEL_WARNING = -120 , U_ERROR_WARNING_LIMIT , U_ZERO_ERROR = 0 , U_ILLEGAL_ARGUMENT_ERROR = 1 , U_MISSING_RESOURCE_ERROR = 2 , U_INVALID_FORMAT_ERROR = 3 , U_FILE_ACCESS_ERROR = 4 , U_INTERNAL_PROGRAM_ERROR = 5 , U_MESSAGE_PARSE_ERROR = 6 , U_MEMORY_ALLOCATION_ERROR = 7 , U_INDEX_OUTOFBOUNDS_ERROR = 8 , U_PARSE_ERROR = 9 , U_INVALID_CHAR_FOUND = 10 , U_TRUNCATED_CHAR_FOUND = 11 , U_ILLEGAL_CHAR_FOUND = 12 , U_INVALID_TABLE_FORMAT = 13 , U_INVALID_TABLE_FILE = 14 , U_BUFFER_OVERFLOW_ERROR = 15 , U_UNSUPPORTED_ERROR = 16 , U_RESOURCE_TYPE_MISMATCH = 17 , U_ILLEGAL_ESCAPE_SEQUENCE = 18 , U_UNSUPPORTED_ESCAPE_SEQUENCE = 19 , U_NO_SPACE_AVAILABLE = 20 , U_CE_NOT_FOUND_ERROR = 21 , U_PRIMARY_TOO_LONG_ERROR = 22 , U_STATE_TOO_OLD_ERROR = 23 , U_TOO_MANY_ALIASES_ERROR = 24 , U_ENUM_OUT_OF_SYNC_ERROR = 25 , U_INVARIANT_CONVERSION_ERROR = 26 , U_INVALID_STATE_ERROR = 27 , U_COLLATOR_VERSION_MISMATCH = 28 , U_USELESS_COLLATOR_ERROR = 29 , U_NO_WRITE_PERMISSION = 30 , U_INPUT_TOO_LONG_ERROR = 31 , U_STANDARD_ERROR_LIMIT = 32 , U_BAD_VARIABLE_DEFINITION =0x10000 , U_PARSE_ERROR_START = 0x10000 , U_MALFORMED_RULE , U_MALFORMED_SET , U_MALFORMED_SYMBOL_REFERENCE , U_MALFORMED_UNICODE_ESCAPE , U_MALFORMED_VARIABLE_DEFINITION , U_MALFORMED_VARIABLE_REFERENCE , U_MISMATCHED_SEGMENT_DELIMITERS , U_MISPLACED_ANCHOR_START , U_MISPLACED_CURSOR_OFFSET , U_MISPLACED_QUANTIFIER , U_MISSING_OPERATOR , U_MISSING_SEGMENT_CLOSE , U_MULTIPLE_ANTE_CONTEXTS , U_MULTIPLE_CURSORS , U_MULTIPLE_POST_CONTEXTS , U_TRAILING_BACKSLASH , U_UNDEFINED_SEGMENT_REFERENCE , U_UNDEFINED_VARIABLE , U_UNQUOTED_SPECIAL , U_UNTERMINATED_QUOTE , U_RULE_MASK_ERROR , U_MISPLACED_COMPOUND_FILTER , U_MULTIPLE_COMPOUND_FILTERS , U_INVALID_RBT_SYNTAX , U_INVALID_PROPERTY_PATTERN , U_MALFORMED_PRAGMA , U_UNCLOSED_SEGMENT , U_ILLEGAL_CHAR_IN_SEGMENT , U_VARIABLE_RANGE_EXHAUSTED , U_VARIABLE_RANGE_OVERLAP , U_ILLEGAL_CHARACTER , U_INTERNAL_TRANSLITERATOR_ERROR , U_INVALID_ID , U_INVALID_FUNCTION , U_PARSE_ERROR_LIMIT , U_UNEXPECTED_TOKEN =0x10100 , U_FMT_PARSE_ERROR_START =0x10100 , U_MULTIPLE_DECIMAL_SEPARATORS , U_MULTIPLE_DECIMAL_SEPERATORS = U_MULTIPLE_DECIMAL_SEPARATORS , U_MULTIPLE_EXPONENTIAL_SYMBOLS , U_MALFORMED_EXPONENTIAL_PATTERN , U_MULTIPLE_PERCENT_SYMBOLS , U_MULTIPLE_PERMILL_SYMBOLS , U_MULTIPLE_PAD_SPECIFIERS , U_PATTERN_SYNTAX_ERROR , U_ILLEGAL_PAD_POSITION , U_UNMATCHED_BRACES , U_UNSUPPORTED_PROPERTY , U_UNSUPPORTED_ATTRIBUTE , U_ARGUMENT_TYPE_MISMATCH , U_DUPLICATE_KEYWORD , U_UNDEFINED_KEYWORD , U_DEFAULT_KEYWORD_MISSING , U_DECIMAL_NUMBER_SYNTAX_ERROR , U_FORMAT_INEXACT_ERROR , U_NUMBER_ARG_OUTOFBOUNDS_ERROR , U_NUMBER_SKELETON_SYNTAX_ERROR , U_MF_UNRESOLVED_VARIABLE_ERROR , U_MF_SYNTAX_ERROR , U_MF_UNKNOWN_FUNCTION_ERROR , U_MF_VARIANT_KEY_MISMATCH_ERROR , U_MF_FORMATTING_ERROR , U_MF_NONEXHAUSTIVE_PATTERN_ERROR , U_MF_DUPLICATE_OPTION_NAME_ERROR , U_MF_SELECTOR_ERROR , U_MF_MISSING_SELECTOR_ANNOTATION_ERROR , U_MF_DUPLICATE_DECLARATION_ERROR , U_MF_OPERAND_MISMATCH_ERROR , U_MF_DUPLICATE_VARIANT_ERROR , U_MF_BAD_OPTION , U_FMT_PARSE_ERROR_LIMIT = 0x10121 , U_BRK_INTERNAL_ERROR =0x10200 , U_BRK_ERROR_START =0x10200 , U_BRK_HEX_DIGITS_EXPECTED , U_BRK_SEMICOLON_EXPECTED , U_BRK_RULE_SYNTAX , U_BRK_UNCLOSED_SET , U_BRK_ASSIGN_ERROR , U_BRK_VARIABLE_REDFINITION , U_BRK_MISMATCHED_PAREN , U_BRK_NEW_LINE_IN_QUOTED_STRING , U_BRK_UNDEFINED_VARIABLE , U_BRK_INIT_ERROR , U_BRK_RULE_EMPTY_SET , U_BRK_UNRECOGNIZED_OPTION , U_BRK_MALFORMED_RULE_TAG , U_BRK_ERROR_LIMIT , U_REGEX_INTERNAL_ERROR =0x10300 , U_REGEX_ERROR_START =0x10300 , U_REGEX_RULE_SYNTAX , U_REGEX_INVALID_STATE , U_REGEX_BAD_ESCAPE_SEQUENCE , U_REGEX_PROPERTY_SYNTAX , U_REGEX_UNIMPLEMENTED , U_REGEX_MISMATCHED_PAREN , U_REGEX_NUMBER_TOO_BIG , U_REGEX_BAD_INTERVAL , U_REGEX_MAX_LT_MIN , U_REGEX_INVALID_BACK_REF , U_REGEX_INVALID_FLAG , U_REGEX_LOOK_BEHIND_LIMIT , U_REGEX_SET_CONTAINS_STRING , U_REGEX_OCTAL_TOO_BIG , U_REGEX_MISSING_CLOSE_BRACKET =U_REGEX_SET_CONTAINS_STRING+2 , U_REGEX_INVALID_RANGE , U_REGEX_STACK_OVERFLOW , U_REGEX_TIME_OUT , U_REGEX_STOPPED_BY_CALLER , U_REGEX_PATTERN_TOO_BIG , U_REGEX_INVALID_CAPTURE_GROUP_NAME , U_REGEX_ERROR_LIMIT =U_REGEX_STOPPED_BY_CALLER+3 , U_IDNA_PROHIBITED_ERROR =0x10400 , U_IDNA_ERROR_START =0x10400 , U_IDNA_UNASSIGNED_ERROR , U_IDNA_CHECK_BIDI_ERROR , U_IDNA_STD3_ASCII_RULES_ERROR , U_IDNA_ACE_PREFIX_ERROR , U_IDNA_VERIFICATION_ERROR , U_IDNA_LABEL_TOO_LONG_ERROR , U_IDNA_ZERO_LENGTH_LABEL_ERROR , U_IDNA_DOMAIN_NAME_TOO_LONG_ERROR , U_IDNA_ERROR_LIMIT , U_STRINGPREP_PROHIBITED_ERROR = U_IDNA_PROHIBITED_ERROR , U_STRINGPREP_UNASSIGNED_ERROR = U_IDNA_UNASSIGNED_ERROR , U_STRINGPREP_CHECK_BIDI_ERROR = U_IDNA_CHECK_BIDI_ERROR , U_PLUGIN_ERROR_START =0x10500 , U_PLUGIN_TOO_HIGH =0x10500 , U_PLUGIN_DIDNT_SET_LEVEL , U_PLUGIN_ERROR_LIMIT , U_ERROR_LIMIT =U_PLUGIN_ERROR_LIMIT }
| Standard ICU4C error code type, a substitute for exceptions. More...

## Functions
U_CAPI const char * | u_errorName (UErrorCode code)
| Return a string for a UErrorCode value. More...

## Detailed Description

Basic definitions for ICU, for both C and C++ APIs.

This file defines basic types, constants, and enumerations directly or indirectly by including other header files, especially utf.h for the basic character and string definitions and umachine.h for consistent integer and other types.

Definition in file utypes.h.

## Macro Definition Documentation

## ◆ NULL

#define NULL ((void *)0)

Define NULL if necessary, to nullptr for C++ and to ((void *)0) for C.

Stable:
  ICU 2.0

Definition at line 203 of file utypes.h.

## ◆ U_COMBINED_IMPLEMENTATION

#define U_COMBINED_IMPLEMENTATION 1

Set to export library symbols from inside the ICU library when all of ICU is in a single library.

This can be set as a compiler option while building ICU, and it needs to be the first one tested to override U_COMMON_API, U_I18N_API, etc.

Stable:
  ICU 2.0

Definition at line 310 of file utypes.h.

## ◆ U_COMMON_API

#define U_COMMON_API U_EXPORT

Set to export library symbols from inside the common library, and to import them from outside.

Stable:
  ICU 2.0

Definition at line 315 of file utypes.h.

## ◆ U_COMMON_API_CLASS

#define U_COMMON_API_CLASS U_COMMON_API

Set to export library symbols from inside the common library, and to import them from outside, to be used on a class.

Draft:
  This API may be changed in the future versions and was introduced in ICU 78

Definition at line 456 of file utypes.h.

## ◆ U_DATA_API

#define U_DATA_API U_EXPORT

Set to export library symbols from inside the stubdata library, and to import them from outside.

Stable:
  ICU 3.0

Definition at line 314 of file utypes.h.

## ◆ U_DATA_API_CLASS

#define U_DATA_API_CLASS U_DATA_API

Set to export library symbols from inside the stubdata library, and to import them from outside, to be used on a class.

Draft:
  This API may be changed in the future versions and was introduced in ICU 78

Definition at line 455 of file utypes.h.

## ◆ U_DATE_MAX

#define U_DATE_MAX DBL_MAX

Maximum UDate value.

Stable:
  ICU 4.8

Definition at line 233 of file utypes.h.

## ◆ U_DATE_MIN

#define U_DATE_MIN -U_DATE_MAX

Minimum UDate value.

Stable:
  ICU 4.8

Definition at line 239 of file utypes.h.

## ◆ U_FAILURE

#define U_FAILURE | ( |  | x | ) | ((x)>U_ZERO_ERROR)

Does the error code indicate a failure?

Stable:
  ICU 2.0

Definition at line 827 of file utypes.h.

## ◆ U_HIDE_DRAFT_API

#define U_HIDE_DRAFT_API 1

Define this to 1 to request that draft API be "hidden".

Internal:
  Do not use.

This API is for internal use only.

Definition at line 99 of file utypes.h.

## ◆ U_HIDE_INTERNAL_API

#define U_HIDE_INTERNAL_API 1

Define this to 1 to request that internal API be "hidden".

Internal:
  Do not use.

This API is for internal use only.

Definition at line 102 of file utypes.h.

## ◆ U_I18N_API

#define U_I18N_API U_EXPORT

Set to export library symbols from inside the i18n library, and to import them from outside.

Stable:
  ICU 2.0

Definition at line 316 of file utypes.h.

## ◆ U_I18N_API_CLASS

#define U_I18N_API_CLASS U_I18N_API

Set to export library symbols from inside the i18n library, and to import them from outside, to be used on a class.

Draft:
  This API may be changed in the future versions and was introduced in ICU 78

Definition at line 457 of file utypes.h.

## ◆ U_ICUDATA_ENTRY_POINT

#define U_ICUDATA_ENTRY_POINT U_DEF2_ICUDATA_ENTRY_POINT(U_ICU_VERSION_MAJOR_NUM,U_LIB_SUFFIX_C_NAME)

U_ICU_ENTRY_POINT is the name of the DLL entry point to the ICU data library.

Defined as a literal, not a string. Tricky Preprocessor use - ## operator replaces macro parameters with the literal string from the corresponding macro invocation, before other macro substitutions. Need a nested #defines to get the actual version numbers rather than the literal text U_ICU_VERSION_MAJOR_NUM into the name. The net result will be something of the form #define U_ICU_ENTRY_POINT icudt19_dat

Stable:
  ICU 2.4

Definition at line 171 of file utypes.h.

## ◆ U_ICUDATA_NAME

#define U_ICUDATA_NAME "icudt" U_ICU_VERSION_SHORT U_ICUDATA_TYPE_LETTER

A single string literal containing the icudata stub name.

i.e. 'icudt18e' for ICU 1.8.x on EBCDIC, etc..

Stable:
  ICU 2.0

Definition at line 154 of file utypes.h.

## ◆ U_ICUDATA_TYPE_LETTER

#define U_ICUDATA_TYPE_LETTER "l"

This is a platform-dependent string containing one letter:

- b for big-endian, ASCII-family platforms
- l for little-endian, ASCII-family platforms
- e for big-endian, EBCDIC-family platforms This letter is part of the common data file name.
  Stable:
    ICU 2.0

Definition at line 144 of file utypes.h.

## ◆ U_ICUDATA_TYPE_LITLETTER

#define U_ICUDATA_TYPE_LITLETTER l

The non-string form of U_ICUDATA_TYPE_LETTER.

Stable:
  ICU 2.0

Definition at line 145 of file utypes.h.

## ◆ U_IO_API

#define U_IO_API U_EXPORT

Set to export library symbols from inside the ustdio library, and to import them from outside.

Stable:
  ICU 2.0

Definition at line 319 of file utypes.h.

## ◆ U_IO_API_CLASS

#define U_IO_API_CLASS U_IO_API

Set to export library symbols from inside the ustdio library, and to import them from outside, to be used on a class.

Draft:
  This API may be changed in the future versions and was introduced in ICU 78

Definition at line 460 of file utypes.h.

## ◆ U_LAYOUT_API

#define U_LAYOUT_API U_EXPORT

Set to export library symbols from inside the layout engine library, and to import them from outside.

Stable:
  ICU 2.0

Definition at line 317 of file utypes.h.

## ◆ U_LAYOUT_API_CLASS

#define U_LAYOUT_API_CLASS U_LAYOUT_API

Set to export library symbols from inside the layout engine library, and to import them from outside, to be used on a class.

Draft:
  This API may be changed in the future versions and was introduced in ICU 78

Definition at line 458 of file utypes.h.

## ◆ U_LAYOUTEX_API

#define U_LAYOUTEX_API U_EXPORT

Set to export library symbols from inside the layout extensions library, and to import them from outside.

Stable:
  ICU 2.6

Definition at line 318 of file utypes.h.

## ◆ U_LAYOUTEX_API_CLASS

#define U_LAYOUTEX_API_CLASS U_LAYOUTEX_API

Set to export library symbols from inside the layout extensions library, and to import them from outside, to be used on a class.

Draft:
  This API may be changed in the future versions and was introduced in ICU 78

Definition at line 459 of file utypes.h.

## ◆ U_MILLIS_PER_DAY

#define U_MILLIS_PER_DAY (86400000)

The number of milliseconds per day.

Stable:
  ICU 2.0

Definition at line 227 of file utypes.h.

## ◆ U_MILLIS_PER_HOUR

#define U_MILLIS_PER_HOUR (3600000)

The number of milliseconds per hour.

Stable:
  ICU 2.0

Definition at line 225 of file utypes.h.

## ◆ U_MILLIS_PER_MINUTE

#define U_MILLIS_PER_MINUTE (60000)

The number of milliseconds per minute.

Stable:
  ICU 2.0

Definition at line 223 of file utypes.h.

## ◆ U_MILLIS_PER_SECOND

#define U_MILLIS_PER_SECOND (1000)

The number of milliseconds per second.

Stable:
  ICU 2.0

Definition at line 221 of file utypes.h.

## ◆ U_SHOW_CPLUSPLUS_API

#define U_SHOW_CPLUSPLUS_API 0

When defined to 1 (=default) and compiled with a C++ compiler, both C and C++ APIs are visible.

API visibility control Otherwise, only C APIs are visible; this is for C++ users who want to restrict their usage to binary stable C APIs exported by ICU DLLs.

Internal:
  Do not use. This API is for internal use only.

Definition at line 83 of file utypes.h.

## ◆ U_SHOW_CPLUSPLUS_HEADER_API

#define U_SHOW_CPLUSPLUS_HEADER_API 0

When defined to 1 (=default) and compiled with a C++ compiler, C++ header-only APIs are visible.

This is for C++ users who restrict their usage to binary stable C APIs exported by ICU DLLs (U_SHOW_CPLUSPLUS_API=0) but who still want to use C++ header-only APIs which do not rely on ICU DLL exports.

Internal:
  Do not use. This API is for internal use only.

Definition at line 85 of file utypes.h.

## ◆ U_STANDARD_CPP_NAMESPACE

#define U_STANDARD_CPP_NAMESPACE

Control of C++ Namespace.

Stable:
  ICU 2.0

Definition at line 474 of file utypes.h.

## ◆ U_SUCCESS

#define U_SUCCESS | ( |  | x | ) | ((x)<=U_ZERO_ERROR)

Does the error code indicate success?

Stable:
  ICU 2.0

Definition at line 822 of file utypes.h.

## ◆ U_TOOLUTIL_API

#define U_TOOLUTIL_API U_EXPORT

Set to export library symbols from inside the toolutil library, and to import them from outside.

Stable:
  ICU 3.4

Definition at line 320 of file utypes.h.

## ◆ U_TOOLUTIL_API_CLASS

#define U_TOOLUTIL_API_CLASS U_TOOLUTIL_API

Set to export library symbols from inside the toolutil library, and to import them from outside, to be used on a class.

Draft:
  This API may be changed in the future versions and was introduced in ICU 78

Definition at line 461 of file utypes.h.

## Typedef Documentation

## ◆ UDate

typedef double UDate

Date and Time data type.

This is a primitive data type that holds the date and time as the number of milliseconds since 1970-jan-01, 00:00 UTC. UTC leap seconds are ignored.

Stable:
  ICU 2.0

Definition at line 218 of file utypes.h.

## ◆ UErrorCode

typedef enum UErrorCode UErrorCode

Standard ICU4C error code type, a substitute for exceptions.

Initialize the UErrorCode with U_ZERO_ERROR, and check for success or failure using U_SUCCESS() or U_FAILURE():

    UErrorCode errorCode = U_ZERO_ERROR;
    // call ICU API that needs an error code parameter.
    if (U_FAILURE(errorCode)) {
        // An error occurred. Handle it here.
    }

C++ code should use icu::ErrorCode, available in unicode/errorcode.h, or a suitable subclass.

For more information, see: https://unicode-org.github.io/icu/userguide/dev/codingguidelines#details-about-icu-error-codes

Note: By convention, ICU functions that take a reference (C++) or a pointer (C) to a UErrorCode first test:

    if (U_FAILURE(errorCode)) { return immediately; }

so that in a chain of such functions the first one that sets an error code causes the following ones to not perform any operations.

Stable:
  ICU 2.0

## Enumeration Type Documentation

## ◆ UErrorCode

enum UErrorCode

Standard ICU4C error code type, a substitute for exceptions.

Initialize the UErrorCode with U_ZERO_ERROR, and check for success or failure using U_SUCCESS() or U_FAILURE():

    UErrorCode errorCode = U_ZERO_ERROR;
    // call ICU API that needs an error code parameter.
    if (U_FAILURE(errorCode)) {
        // An error occurred. Handle it here.
    }

C++ code should use icu::ErrorCode, available in unicode/errorcode.h, or a suitable subclass.

For more information, see: https://unicode-org.github.io/icu/userguide/dev/codingguidelines#details-about-icu-error-codes

Note: By convention, ICU functions that take a reference (C++) or a pointer (C) to a UErrorCode first test:

    if (U_FAILURE(errorCode)) { return immediately; }

so that in a chain of such functions the first one that sets an error code causes the following ones to not perform any operations.

Stable:
  ICU 2.0

Enumerator
U_USING_FALLBACK_WARNING | A resource bundle lookup returned a fallback result (not an error)
U_ERROR_WARNING_START | Start of information results (semantically successful)
U_USING_DEFAULT_WARNING | A resource bundle lookup returned a result from the root locale (not an error)
U_SAFECLONE_ALLOCATED_WARNING | A SafeClone operation required allocating memory (informational only)
U_STATE_OLD_WARNING | ICU has to use compatibility layer to construct the service. Expect performance/memory usage degradation. Consider upgrading
U_STRING_NOT_TERMINATED_WARNING | An output string could not be NUL-terminated because output length==destCapacity.
U_SORT_KEY_TOO_SHORT_WARNING | Number of levels requested in getBound is higher than the number of levels in the sort key.
U_AMBIGUOUS_ALIAS_WARNING | This converter alias can go to different converter implementations.
U_DIFFERENT_UCA_VERSION | ucol_open encountered a mismatch between UCA version and collator image version, so the collator was constructed from rules. No impact to further function
U_PLUGIN_CHANGED_LEVEL_WARNING | A plugin caused a level change. May not be an error, but later plugins may not load.
U_ERROR_WARNING_LIMIT | One more than the highest normal UErrorCode warning value. Deprecated: ICU 58 The numeric value may change over time, see ICU ticket #12420.
U_ZERO_ERROR | No error, no warning.
U_ILLEGAL_ARGUMENT_ERROR | Start of codes indicating failure.
U_MISSING_RESOURCE_ERROR | The requested resource cannot be found.
U_INVALID_FORMAT_ERROR | Data format is not what is expected.
U_FILE_ACCESS_ERROR | The requested file cannot be found.
U_INTERNAL_PROGRAM_ERROR | Indicates a bug in the library code.
U_MESSAGE_PARSE_ERROR | Unable to parse a message (message format)
U_MEMORY_ALLOCATION_ERROR | Memory allocation error.
U_INDEX_OUTOFBOUNDS_ERROR | Trying to access the index that is out of bounds.
U_PARSE_ERROR | Equivalent to Java ParseException.
U_INVALID_CHAR_FOUND | Character conversion: Unmappable input sequence. In other APIs: Invalid character.
U_TRUNCATED_CHAR_FOUND | Character conversion: Incomplete input sequence.
U_ILLEGAL_CHAR_FOUND | Character conversion: Illegal input sequence/combination of input units.
U_INVALID_TABLE_FORMAT | Conversion table file found, but corrupted.
U_INVALID_TABLE_FILE | Conversion table file not found.
U_BUFFER_OVERFLOW_ERROR | A result would not fit in the supplied buffer.
U_UNSUPPORTED_ERROR | Requested operation not supported in current context.
U_RESOURCE_TYPE_MISMATCH | an operation is requested over a resource that does not support it
U_ILLEGAL_ESCAPE_SEQUENCE | ISO-2022 illegal escape sequence.
U_UNSUPPORTED_ESCAPE_SEQUENCE | ISO-2022 unsupported escape sequence.
U_NO_SPACE_AVAILABLE | No space available for in-buffer expansion for Arabic shaping.
U_CE_NOT_FOUND_ERROR | Currently used only while setting variable top, but can be used generally.
U_PRIMARY_TOO_LONG_ERROR | User tried to set variable top to a primary that is longer than two bytes.
U_STATE_TOO_OLD_ERROR | ICU cannot construct a service from this state, as it is no longer supported.
U_TOO_MANY_ALIASES_ERROR | There are too many aliases in the path to the requested resource. It is very possible that a circular alias definition has occurred
U_ENUM_OUT_OF_SYNC_ERROR | UEnumeration out of sync with underlying collection.
U_INVARIANT_CONVERSION_ERROR | Unable to convert a UChar* string to char* with the invariant converter.
U_INVALID_STATE_ERROR | Requested operation can not be completed with ICU in its current state.
U_COLLATOR_VERSION_MISMATCH | Collator version is not compatible with the base version.
U_USELESS_COLLATOR_ERROR | Collator is options only and no base is specified.
U_NO_WRITE_PERMISSION | Attempt to modify read-only or constant data.
U_INPUT_TOO_LONG_ERROR | The input is impractically long for an operation. It is rejected because it may lead to problems such as excessive processing time, stack depth, or heap memory requirements. Stable: ICU 68
U_STANDARD_ERROR_LIMIT | One more than the highest standard error code. Deprecated: ICU 58 The numeric value may change over time, see ICU ticket #12420.
U_BAD_VARIABLE_DEFINITION | Missing '$' or duplicate variable name.
U_PARSE_ERROR_START | Start of Transliterator errors.
U_MALFORMED_RULE | Elements of a rule are misplaced.
U_MALFORMED_SET | A UnicodeSet pattern is invalid.
U_MALFORMED_SYMBOL_REFERENCE | UNUSED as of ICU 2.4.
U_MALFORMED_UNICODE_ESCAPE | A Unicode escape pattern is invalid.
U_MALFORMED_VARIABLE_DEFINITION | A variable definition is invalid.
U_MALFORMED_VARIABLE_REFERENCE | A variable reference is invalid.
U_MISMATCHED_SEGMENT_DELIMITERS | UNUSED as of ICU 2.4.
U_MISPLACED_ANCHOR_START | A start anchor appears at an illegal position.
U_MISPLACED_CURSOR_OFFSET | A cursor offset occurs at an illegal position.
U_MISPLACED_QUANTIFIER | A quantifier appears after a segment close delimiter.
U_MISSING_OPERATOR | A rule contains no operator.
U_MISSING_SEGMENT_CLOSE | UNUSED as of ICU 2.4.
U_MULTIPLE_ANTE_CONTEXTS | More than one ante context.
U_MULTIPLE_CURSORS | More than one cursor.
U_MULTIPLE_POST_CONTEXTS | More than one post context.
U_TRAILING_BACKSLASH | A dangling backslash.
U_UNDEFINED_SEGMENT_REFERENCE | A segment reference does not correspond to a defined segment.
U_UNDEFINED_VARIABLE | A variable reference does not correspond to a defined variable.
U_UNQUOTED_SPECIAL | A special character was not quoted or escaped.
U_UNTERMINATED_QUOTE | A closing single quote is missing.
U_RULE_MASK_ERROR | A rule is hidden by an earlier more general rule.
U_MISPLACED_COMPOUND_FILTER | A compound filter is in an invalid location.
U_MULTIPLE_COMPOUND_FILTERS | More than one compound filter.
U_INVALID_RBT_SYNTAX | A "::id" rule was passed to the RuleBasedTransliterator parser.
U_INVALID_PROPERTY_PATTERN | UNUSED as of ICU 2.4.
U_MALFORMED_PRAGMA | A 'use' pragma is invalid.
U_UNCLOSED_SEGMENT | A closing ')' is missing.
U_ILLEGAL_CHAR_IN_SEGMENT | UNUSED as of ICU 2.4.
U_VARIABLE_RANGE_EXHAUSTED | Too many stand-ins generated for the given variable range.
U_VARIABLE_RANGE_OVERLAP | The variable range overlaps characters used in rules.
U_ILLEGAL_CHARACTER | A special character is outside its allowed context.
U_INTERNAL_TRANSLITERATOR_ERROR | Internal transliterator system error.
U_INVALID_ID | A "::id" rule specifies an unknown transliterator.
U_INVALID_FUNCTION | A "&fn()" rule specifies an unknown transliterator.
U_PARSE_ERROR_LIMIT | One more than the highest normal Transliterator error code. Deprecated: ICU 58 The numeric value may change over time, see ICU ticket #12420.
U_UNEXPECTED_TOKEN | Syntax error in format pattern.
U_FMT_PARSE_ERROR_START | Start of format library errors.
U_MULTIPLE_DECIMAL_SEPARATORS | More than one decimal separator in number pattern.
U_MULTIPLE_DECIMAL_SEPERATORS | Typo: kept for backward compatibility. Use U_MULTIPLE_DECIMAL_SEPARATORS
U_MULTIPLE_EXPONENTIAL_SYMBOLS | More than one exponent symbol in number pattern.
U_MALFORMED_EXPONENTIAL_PATTERN | Grouping symbol in exponent pattern.
U_MULTIPLE_PERCENT_SYMBOLS | More than one percent symbol in number pattern.
U_MULTIPLE_PERMILL_SYMBOLS | More than one permill symbol in number pattern.
U_MULTIPLE_PAD_SPECIFIERS | More than one pad symbol in number pattern.
U_PATTERN_SYNTAX_ERROR | Syntax error in format pattern.
U_ILLEGAL_PAD_POSITION | Pad symbol misplaced in number pattern.
U_UNMATCHED_BRACES | Braces do not match in message pattern.
U_UNSUPPORTED_PROPERTY | UNUSED as of ICU 2.4.
U_UNSUPPORTED_ATTRIBUTE | UNUSED as of ICU 2.4.
U_ARGUMENT_TYPE_MISMATCH | Argument name and argument index mismatch in MessageFormat functions.
U_DUPLICATE_KEYWORD | Duplicate keyword in PluralFormat.
U_UNDEFINED_KEYWORD | Undefined Plural keyword.
U_DEFAULT_KEYWORD_MISSING | Missing DEFAULT rule in plural rules.
U_DECIMAL_NUMBER_SYNTAX_ERROR | Decimal number syntax error.
U_FORMAT_INEXACT_ERROR | Cannot format a number exactly and rounding mode is ROUND_UNNECESSARY. Stable: ICU 4.8
U_NUMBER_ARG_OUTOFBOUNDS_ERROR | The argument to a NumberFormatter helper method was out of bounds; the bounds are usually 0 to 999. Stable: ICU 61
U_NUMBER_SKELETON_SYNTAX_ERROR | The number skeleton passed to C++ NumberFormatter or C UNumberFormatter was invalid or contained a syntax error. Stable: ICU 62
U_MF_UNRESOLVED_VARIABLE_ERROR | A variable is referred to but not bound by any definition. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_SYNTAX_ERROR | Includes all syntax errors. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_UNKNOWN_FUNCTION_ERROR | An annotation refers to a function not defined by the standard or custom function registry. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_VARIANT_KEY_MISMATCH_ERROR | In a match-construct, one or more variants had a different number of keys from the number of selectors. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_FORMATTING_ERROR | Covers all runtime errors: for example, an internally inconsistent set of options. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_NONEXHAUSTIVE_PATTERN_ERROR | In a match-construct, the variants do not cover all possible values. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_DUPLICATE_OPTION_NAME_ERROR | In an annotation, the same option name appears more than once. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_SELECTOR_ERROR | A selector function is applied to an operand of the wrong type. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_MISSING_SELECTOR_ANNOTATION_ERROR | A selector expression evaluates to an unannotated operand. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_DUPLICATE_DECLARATION_ERROR | The same variable is declared in more than one .local or .input declaration. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_OPERAND_MISMATCH_ERROR | An operand provided to a function does not have the required form for that function. Internal: Do not use. This API is for internal use only. ICU 75 technology preview Deprecated: This API is for technology preview only.
U_MF_DUPLICATE_VARIANT_ERROR | A message includes a variant with the same key list as another variant. Internal: Do not use. This API is for internal use only. ICU 76 technology preview Deprecated: This API is for technology preview only.
U_MF_BAD_OPTION | An option value provided to a function does not have the required form for that option. Internal: Do not use. This API is for internal use only. ICU 77 technology preview Deprecated: This API is for technology preview only.
U_FMT_PARSE_ERROR_LIMIT | One more than the highest normal formatting API error code. Deprecated: ICU 58 The numeric value may change over time, see ICU ticket #12420.
U_BRK_INTERNAL_ERROR | An internal error (bug) was detected.
U_BRK_ERROR_START | Start of codes indicating Break Iterator failures.
U_BRK_HEX_DIGITS_EXPECTED | Hex digits expected as part of a escaped char in a rule.
U_BRK_SEMICOLON_EXPECTED | Missing ';' at the end of a RBBI rule.
U_BRK_RULE_SYNTAX | Syntax error in RBBI rule.
U_BRK_UNCLOSED_SET | UnicodeSet writing an RBBI rule missing a closing ']'.
U_BRK_ASSIGN_ERROR | Syntax error in RBBI rule assignment statement.
U_BRK_VARIABLE_REDFINITION | RBBI rule $Variable redefined.
U_BRK_MISMATCHED_PAREN | Mis-matched parentheses in an RBBI rule.
U_BRK_NEW_LINE_IN_QUOTED_STRING | Missing closing quote in an RBBI rule.
U_BRK_UNDEFINED_VARIABLE | Use of an undefined $Variable in an RBBI rule.
U_BRK_INIT_ERROR | Initialization failure. Probable missing ICU Data.
U_BRK_RULE_EMPTY_SET | Rule contains an empty Unicode Set.
U_BRK_UNRECOGNIZED_OPTION | !!option in RBBI rules not recognized.
U_BRK_MALFORMED_RULE_TAG | The {nnn} tag on a rule is malformed
U_BRK_ERROR_LIMIT | One more than the highest normal BreakIterator error code. Deprecated: ICU 58 The numeric value may change over time, see ICU ticket #12420.
U_REGEX_INTERNAL_ERROR | An internal error (bug) was detected.
U_REGEX_ERROR_START | Start of codes indicating Regexp failures
U_REGEX_RULE_SYNTAX | Syntax error in regexp pattern.
U_REGEX_INVALID_STATE | RegexMatcher in invalid state for requested operation.
U_REGEX_BAD_ESCAPE_SEQUENCE | Unrecognized backslash escape sequence in pattern
U_REGEX_PROPERTY_SYNTAX | Incorrect Unicode property
U_REGEX_UNIMPLEMENTED | Use of regexp feature that is not yet implemented.
U_REGEX_MISMATCHED_PAREN | Incorrectly nested parentheses in regexp pattern.
U_REGEX_NUMBER_TOO_BIG | Decimal number is too large.
U_REGEX_BAD_INTERVAL | Error in {min,max} interval
U_REGEX_MAX_LT_MIN | In {min,max}, max is less than min.
U_REGEX_INVALID_BACK_REF | Back-reference to a non-existent capture group.
U_REGEX_INVALID_FLAG | Invalid value for match mode flags.
U_REGEX_LOOK_BEHIND_LIMIT | Look-Behind pattern matches must have a bounded maximum length.
U_REGEX_SET_CONTAINS_STRING | Regexps cannot have UnicodeSets containing strings.
U_REGEX_OCTAL_TOO_BIG | Octal character constants must be <= 0377. Deprecated: ICU 54. This error cannot occur.
U_REGEX_MISSING_CLOSE_BRACKET | Missing closing bracket on a bracket expression.
U_REGEX_INVALID_RANGE | In a character range [x-y], x is greater than y.
U_REGEX_STACK_OVERFLOW | Regular expression backtrack stack overflow.
U_REGEX_TIME_OUT | Maximum allowed match time exceeded
U_REGEX_STOPPED_BY_CALLER | Matching operation aborted by user callback fn.
U_REGEX_PATTERN_TOO_BIG | Pattern exceeds limits on size or complexity. Stable: ICU 55
U_REGEX_INVALID_CAPTURE_GROUP_NAME | Invalid capture group name. Stable: ICU 55
U_REGEX_ERROR_LIMIT | One more than the highest normal regular expression error code. Deprecated: ICU 58 The numeric value may change over time, see ICU ticket #12420.
U_IDNA_ERROR_LIMIT | One more than the highest normal IDNA error code. Deprecated: ICU 58 The numeric value may change over time, see ICU ticket #12420.
U_PLUGIN_ERROR_START | Start of codes indicating plugin failures.
U_PLUGIN_TOO_HIGH | The plugin's level is too high to be loaded right now.
U_PLUGIN_DIDNT_SET_LEVEL | The plugin didn't call uplug_setPlugLevel in response to a QUERY.
U_PLUGIN_ERROR_LIMIT | One more than the highest normal plug-in error code. Deprecated: ICU 58 The numeric value may change over time, see ICU ticket #12420.
U_ERROR_LIMIT | One more than the highest normal error code. Deprecated: ICU 58 The numeric value may change over time, see ICU ticket #12420.

Definition at line 509 of file utypes.h.

## Function Documentation

## ◆ u_errorName()

U_CAPI const char* u_errorName | ( | UErrorCode | code | ) |

Return a string for a UErrorCode value.

The string will be the same as the name of the error code constant in the UErrorCode enum above.

Stable:
  ICU 2.0