This section lists the constants and types defined by the Support Kit and used throughout the entire Be operating system. Not included here are constants used as status_t values (error codes). They're listed in Error Codes .
Declared in: be/support/SupportDefs.h
| Constant | Value |
|---|---|
| false | 0 |
| true | 1 |
These constants are defined as values for the bool type (described in the next section). The BeOS defines them for C code only. Because they match the boolean symbols that are part of the C++ language, they let you use the same bool type and true and false values when programming in both languages.
See also: bool
Declared in: be/support/ByteSwap.h
| Constant | Description |
|---|---|
| B_SWAP_HOST_TO_LENDIAN | Convert from host byte order to little endian |
| B_SWAP_HOST_TO_BENDIAN | Convert from host byte order to big endian |
| B_SWAP_LENDIAN_TO_HOST | Convert from little endian to host byte order |
| B_SWAP_BENDIAN_TO_HOST | Convert from big endian to host byte order |
| B_SWAP_ALWAYS | Always convert endianness |
These constants define the action to be taken by the swap_data() general byte swapping function.
See also: swap_data()
Declared in: be/support/UTF8.h
These constants identify character encodings to the convert_to_utf8() and convert_from_utf8() functions, which convert text to and from the standard UTF8 character encoding assumed by the BeOS. The identify the source encoding for a conversion to UTF-8 and the destination encoding for a conversion from UTF-8.
See also: convert_to_utf8(), the BFont class in the Interface Kit
Declared in: be/support/SupportDefs.h
const char *B_EMPTY_STRING
This constant provides a global pointer to an empty string ("").
Declared in: be/support/SupportDefs.h
| Constant | Value |
|---|---|
| NIL | 0 |
| NULL | 0 |
These constants represent "empty" values. They're synonyms that can be used interchangeably.
Declared in: be/support/TypeConstants.h
| Constant | Meaning |
|---|---|
| B_CHAR_TYPE | A single character |
| B_INT8_TYPE | An 8-bit integer |
| B_INT16_TYPE | A 16-bit integer |
| B_INT32_TYPE | A 32-bit integer |
| B_INT64_TYPE | A 64-bit integer |
| B_UINT8_TYPE | An unsigned 8-bit integer |
| B_UINT16_TYPE | An unsigned 16-bit integer |
| B_UINT32_TYPE | An unsigned 32-bit integer |
| B_UINT64_TYPE | An unsigned 64-bit integer |
| B_FLOAT_TYPE | A float |
| B_DOUBLE_TYPE | A double |
| B_BOOL_TYPE | A boolean value (the bool type) |
| B_OFF_T_TYPE | An off_t value |
| B_SIZE_T_TYPE | A size_t value |
| B_SSIZE_T_TYPE | An ssize_t value |
| B_POINTER_TYPE | A pointer of some kind (including void *) |
| B_OBJECT_TYPE | An object pointer (such as BMessage *) |
| B_MESSAGE_TYPE | A BMessage object (not BMessage *) |
| B_MESSENGER_TYPE | A BMessenger object |
| B_POINT_TYPE | A BPoint object |
| B_RECT_TYPE | A BRect object |
| B_PATH_TYPE | A BPath object |
| B_REF_TYPE | An entry_ref structure |
| B_RGB_COLOR_TYPE | An rgb_color structure |
| B_PATTERN_TYPE | A pattern structure |
| B_ASCII_TYPE | Text in ASCII format |
| B_STRING_TYPE | A null-terminated character string |
| B_MONOCHROME_1_BIT_TYPE | Raw data for a monochrome bitmap (1 bit/pixel) |
| B_GRAYSCALE_8_BIT_TYPE | Raw data for a grayscale bitmap (8 bits per pixel) |
| B_COLOR_8_BIT_TYPE | Raw bitmap data in the B_COLOR_8_BIT color space |
| B_RGB_32_BIT_TYPE | Raw bitmap data in the B_RGB_32_BIT color space |
| B_TIME_TYPE | 64-bit microsecond time_t data |
| B_RAW_TYPE | Raw, untyped data--a stream of bytes |
| B_MIME_TYPE | The type is specified by a MIME string. |
| B_ANY_TYPE | The type can be any type. |
These constants describe the types of data held by BMessage objects (the Application Kit) and as resources and file system attributes (the Storage Kit). B_ANY_TYPE refers to all types; it indicates that the exact type doesn't matter. B_MIME_TYPE indicates that the name of the data in the BMessage is a MIME string that specifies its true data type. The other constants refer only to a particular type. The type_code defined type marks where these constants are used in the API.
Applications can define their own type codes for data types not found on this list. All the codes the BeOS defines have values formed by concatenating four uppercase letters into a multicharacter constant. For example, B_MESSENGER_TYPE is 'MSNG' and B_SIZE_T_TYPE is 'SIZT'.
See also: type_code
Declared in: be/support/SupportDefs.h
typedef int64 bigtime_t
This type records the time in microseconds as a 64-bit integer. Typically, a bigtime_t variable measures the system time, the number of microseconds since 12:00:00 AM January 1, 1970, UTC (Coordinated Universal Time).
See also: system_time()
Declared in: be/support/SupportDefs.h
typedef unsigned char bool
The C++ language defines bool as its basic boolean type. The BeOS extends the definition to C code, so you can use the same type in both languages. The true and false constants (listed above) are defined as boolean values.
Declared in: be/support/SupportDefs.h
typedef int (*B_PFI)()
typedef long (*B_PFL)()
typedef void (*B_PFV)()
These types define pointers to functions that return int, long, and void values respectively.
Declared in: be/support/Archivable.h
typedef BArchivable *(*instantiation_func) (BMessage *)
This type is a pointer to a function that can instantiate an object from a BMessage archive and return a pointer to the new object. The Instantiate() member function of BArchivable is such a function.
See also: the BArchivable class, find_instantiation_func()
Declared in: be/support/SupportDefs.h
typedef unsigned char uchar
typedef signed char int8
typedef unsigned char uint8
typedef volatile signed char vint8
typedef volatile unsigned char vuint8
typedef short int16
typedef unsigned short uint16
typedef volatile short vint16
typedef volatile unsigned short vuint16
typedef long int32
typedef unsigned long uint32
typedef volatile long vint32
typedef volatile unsigned long vuint32
typedef long long int64
typedef unsigned long long uint64
typedef volatile long long vint64
typedef volatile unsigned long long vuint64
These type names are defined as convenient shorthands for standard integers of various sizes. They're used in place of int, short, and long throughout the BeOS API.
The number at the end of the type name indicates the size of the integer. For example, a uint32 is an unsigned 32-bit value. The type is guaranteed to be defined to its stated size for all platforms (thus their exact definitions may vary from platform to platform).
Using these types will make the code you write more portable. They'll help avoid problems as the operating system and your application move to other platforms.
Declared in: be/support/SupportDefs.h
typedef int32 status_t
This type indicates an error code; it's used mainly for function return values.
See also: "Error Codes"
Declared in: be/support/SupportDefs.h
typedef uint32 type_code
This type is used for the integer codes that indicate a particular data type. The codes--such as B_UINT32_TYPE and B_MIME_TYPE--mark the type of data added to a message or stored as a resource and also appear in other contexts.
See also: Type Codes, the BMessage class in the Application Kit, the BResource class in the Storage Kit
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Last modified November 10, 1998.