SDL 3.0
SDL_iostream.h File Reference
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Data Structures

struct  SDL_IOStreamInterface
 

Typedefs

typedef struct SDL_IOStream SDL_IOStream
 

Enumerations

enum  SDL_IOStatus {
  SDL_IO_STATUS_READY ,
  SDL_IO_STATUS_ERROR ,
  SDL_IO_STATUS_EOF ,
  SDL_IO_STATUS_NOT_READY ,
  SDL_IO_STATUS_READONLY ,
  SDL_IO_STATUS_WRITEONLY
}
 

Functions

Read endian functions

Read an item of the specified endianness and return in native format.

SDL_bool SDL_ReadU8 (SDL_IOStream *src, Uint8 *value)
 
SDL_bool SDL_ReadU16LE (SDL_IOStream *src, Uint16 *value)
 
SDL_bool SDL_ReadS16LE (SDL_IOStream *src, Sint16 *value)
 
SDL_bool SDL_ReadU16BE (SDL_IOStream *src, Uint16 *value)
 
SDL_bool SDL_ReadS16BE (SDL_IOStream *src, Sint16 *value)
 
SDL_bool SDL_ReadU32LE (SDL_IOStream *src, Uint32 *value)
 
SDL_bool SDL_ReadS32LE (SDL_IOStream *src, Sint32 *value)
 
SDL_bool SDL_ReadU32BE (SDL_IOStream *src, Uint32 *value)
 
SDL_bool SDL_ReadS32BE (SDL_IOStream *src, Sint32 *value)
 
SDL_bool SDL_ReadU64LE (SDL_IOStream *src, Uint64 *value)
 
SDL_bool SDL_ReadS64LE (SDL_IOStream *src, Sint64 *value)
 
SDL_bool SDL_ReadU64BE (SDL_IOStream *src, Uint64 *value)
 
SDL_bool SDL_ReadS64BE (SDL_IOStream *src, Sint64 *value)
 
Write endian functions

Write an item of native format to the specified endianness.

SDL_bool SDL_WriteU8 (SDL_IOStream *dst, Uint8 value)
 
SDL_bool SDL_WriteU16LE (SDL_IOStream *dst, Uint16 value)
 
SDL_bool SDL_WriteS16LE (SDL_IOStream *dst, Sint16 value)
 
SDL_bool SDL_WriteU16BE (SDL_IOStream *dst, Uint16 value)
 
SDL_bool SDL_WriteS16BE (SDL_IOStream *dst, Sint16 value)
 
SDL_bool SDL_WriteU32LE (SDL_IOStream *dst, Uint32 value)
 
SDL_bool SDL_WriteS32LE (SDL_IOStream *dst, Sint32 value)
 
SDL_bool SDL_WriteU32BE (SDL_IOStream *dst, Uint32 value)
 
SDL_bool SDL_WriteS32BE (SDL_IOStream *dst, Sint32 value)
 
SDL_bool SDL_WriteU64LE (SDL_IOStream *dst, Uint64 value)
 
SDL_bool SDL_WriteS64LE (SDL_IOStream *dst, Sint64 value)
 
SDL_bool SDL_WriteU64BE (SDL_IOStream *dst, Uint64 value)
 
SDL_bool SDL_WriteS64BE (SDL_IOStream *dst, Sint64 value)
 

IOFrom functions

Functions to create SDL_IOStream structures from various data streams.

#define SDL_PROP_IOSTREAM_WINDOWS_HANDLE_POINTER   "SDL.iostream.windows.handle"
 
#define SDL_PROP_IOSTREAM_STDIO_FILE_POINTER   "SDL.iostream.stdio.file"
 
#define SDL_PROP_IOSTREAM_ANDROID_AASSET_POINTER   "SDL.iostream.android.aasset"
 
#define SDL_PROP_IOSTREAM_DYNAMIC_MEMORY_POINTER   "SDL.iostream.dynamic.memory"
 
#define SDL_PROP_IOSTREAM_DYNAMIC_CHUNKSIZE_NUMBER   "SDL.iostream.dynamic.chunksize"
 
#define SDL_IO_SEEK_SET   0
 
#define SDL_IO_SEEK_CUR   1
 
#define SDL_IO_SEEK_END   2
 
SDL_IOStreamSDL_IOFromFile (const char *file, const char *mode)
 
SDL_IOStreamSDL_IOFromMem (void *mem, size_t size)
 
SDL_IOStreamSDL_IOFromConstMem (const void *mem, size_t size)
 
SDL_IOStreamSDL_IOFromDynamicMem (void)
 
SDL_IOStreamSDL_OpenIO (const SDL_IOStreamInterface *iface, void *userdata)
 
int SDL_CloseIO (SDL_IOStream *context)
 
SDL_PropertiesID SDL_GetIOProperties (SDL_IOStream *context)
 
SDL_IOStatus SDL_GetIOStatus (SDL_IOStream *context)
 
Sint64 SDL_GetIOSize (SDL_IOStream *context)
 
Sint64 SDL_SeekIO (SDL_IOStream *context, Sint64 offset, int whence)
 
Sint64 SDL_TellIO (SDL_IOStream *context)
 
size_t SDL_ReadIO (SDL_IOStream *context, void *ptr, size_t size)
 
size_t SDL_WriteIO (SDL_IOStream *context, const void *ptr, size_t size)
 
size_t SDL_IOprintf (SDL_IOStream *context, SDL_PRINTF_FORMAT_STRING const char *fmt,...) SDL_PRINTF_VARARG_FUNC(2)
 
size_t SDL_IOvprintf (SDL_IOStream *context, SDL_PRINTF_FORMAT_STRING const char *fmt, va_list ap) SDL_PRINTF_VARARG_FUNCV(2)
 
void * SDL_LoadFile_IO (SDL_IOStream *src, size_t *datasize, SDL_bool closeio)
 
void * SDL_LoadFile (const char *file, size_t *datasize)
 

Detailed Description

This file provides a general interface for SDL to read and write data streams. It can easily be extended to files, memory, etc.

SDL_IOStream is not related to the standard C++ iostream class, other than both are abstract interfaces to read/write data.

Definition in file SDL_iostream.h.

Macro Definition Documentation

◆ SDL_IO_SEEK_CUR

#define SDL_IO_SEEK_CUR   1

Seek relative to current read point

Definition at line 359 of file SDL_iostream.h.

◆ SDL_IO_SEEK_END

#define SDL_IO_SEEK_END   2

Seek relative to the end of data

Definition at line 360 of file SDL_iostream.h.

◆ SDL_IO_SEEK_SET

#define SDL_IO_SEEK_SET   0

Seek from the beginning of data

Definition at line 358 of file SDL_iostream.h.

◆ SDL_PROP_IOSTREAM_ANDROID_AASSET_POINTER

#define SDL_PROP_IOSTREAM_ANDROID_AASSET_POINTER   "SDL.iostream.android.aasset"

Definition at line 202 of file SDL_iostream.h.

◆ SDL_PROP_IOSTREAM_DYNAMIC_CHUNKSIZE_NUMBER

#define SDL_PROP_IOSTREAM_DYNAMIC_CHUNKSIZE_NUMBER   "SDL.iostream.dynamic.chunksize"

Definition at line 293 of file SDL_iostream.h.

◆ SDL_PROP_IOSTREAM_DYNAMIC_MEMORY_POINTER

#define SDL_PROP_IOSTREAM_DYNAMIC_MEMORY_POINTER   "SDL.iostream.dynamic.memory"

Definition at line 292 of file SDL_iostream.h.

◆ SDL_PROP_IOSTREAM_STDIO_FILE_POINTER

#define SDL_PROP_IOSTREAM_STDIO_FILE_POINTER   "SDL.iostream.stdio.file"

Definition at line 201 of file SDL_iostream.h.

◆ SDL_PROP_IOSTREAM_WINDOWS_HANDLE_POINTER

#define SDL_PROP_IOSTREAM_WINDOWS_HANDLE_POINTER   "SDL.iostream.windows.handle"

Definition at line 200 of file SDL_iostream.h.

Typedef Documentation

◆ SDL_IOStream

typedef struct SDL_IOStream SDL_IOStream

This is the read/write operation structure – opaque, as of SDL3!

Definition at line 112 of file SDL_iostream.h.

Enumeration Type Documentation

◆ SDL_IOStatus

Enumerator
SDL_IO_STATUS_READY 

Everything is ready

SDL_IO_STATUS_ERROR 

Read or write I/O error

SDL_IO_STATUS_EOF 

End of file

SDL_IO_STATUS_NOT_READY 

Non blocking I/O, not ready

SDL_IO_STATUS_READONLY 

Tried to write a read-only buffer

SDL_IO_STATUS_WRITEONLY 

Tried to read a write-only buffer

Definition at line 46 of file SDL_iostream.h.

47{
48 SDL_IO_STATUS_READY, /**< Everything is ready */
49 SDL_IO_STATUS_ERROR, /**< Read or write I/O error */
50 SDL_IO_STATUS_EOF, /**< End of file */
51 SDL_IO_STATUS_NOT_READY, /**< Non blocking I/O, not ready */
52 SDL_IO_STATUS_READONLY, /**< Tried to write a read-only buffer */
53 SDL_IO_STATUS_WRITEONLY /**< Tried to read a write-only buffer */
SDL_IOStatus
@ SDL_IO_STATUS_ERROR
@ SDL_IO_STATUS_EOF
@ SDL_IO_STATUS_NOT_READY
@ SDL_IO_STATUS_READY
@ SDL_IO_STATUS_WRITEONLY
@ SDL_IO_STATUS_READONLY

Function Documentation

◆ SDL_CloseIO()

int SDL_CloseIO ( SDL_IOStream context)
extern

Close and free an allocated SDL_IOStream structure.

SDL_CloseIO() closes and cleans up the SDL_IOStream stream. It releases any resources used by the stream and frees the SDL_IOStream itself. This returns 0 on success, or -1 if the stream failed to flush to its output (e.g. to disk).

Note that if this fails to flush the stream to disk, this function reports an error, but the SDL_IOStream is still invalid once this function returns.

Parameters
contextSDL_IOStream structure to close
Returns
0 on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_OpenIO

◆ SDL_GetIOProperties()

SDL_PropertiesID SDL_GetIOProperties ( SDL_IOStream context)
extern

Get the properties associated with an SDL_IOStream.

Parameters
contexta pointer to an SDL_IOStream structure
Returns
a valid property ID on success or 0 on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_GetProperty
SDL_SetProperty

◆ SDL_GetIOSize()

Sint64 SDL_GetIOSize ( SDL_IOStream context)
extern

Use this function to get the size of the data stream in an SDL_IOStream.

Parameters
contextthe SDL_IOStream to get the size of the data stream from
Returns
the size of the data stream in the SDL_IOStream on success or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_GetIOStatus()

SDL_IOStatus SDL_GetIOStatus ( SDL_IOStream context)
extern

Query the stream status of an SDL_IOStream.

This information can be useful to decide if a short read or write was due to an error, an EOF, or a non-blocking operation that isn't yet ready to complete.

An SDL_IOStream's status is only expected to change after a SDL_ReadIO or SDL_WriteIO call; don't expect it to change if you just call this query function in a tight loop.

Parameters
contextthe SDL_IOStream to query.
Returns
an SDL_IOStatus enum with the current state.

\threadsafety This function should not be called at the same time that another thread is operating on the same SDL_IOStream.

Since
This function is available since SDL 3.0.0.

◆ SDL_IOFromConstMem()

SDL_IOStream * SDL_IOFromConstMem ( const void *  mem,
size_t  size 
)
extern

Use this function to prepare a read-only memory buffer for use with SDL_IOStream.

This function sets up an SDL_IOStream struct based on a memory area of a certain size. It assumes the memory area is not writable.

Attempting to write to this SDL_IOStream stream will report an error without writing to the memory buffer.

This memory buffer is not copied by the SDL_IOStream; the pointer you provide must remain valid until you close the stream. Closing the stream will not free the original buffer.

If you need to write to a memory buffer, you should use SDL_IOFromMem() with a writable buffer of memory instead.

Parameters
mema pointer to a read-only buffer to feed an SDL_IOStream stream
sizethe buffer size, in bytes
Returns
a pointer to a new SDL_IOStream structure, or NULL if it fails; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_IOFromMem
SDL_CloseIO
SDL_ReadIO
SDL_SeekIO
SDL_TellIO

◆ SDL_IOFromDynamicMem()

SDL_IOStream * SDL_IOFromDynamicMem ( void  )
extern

Use this function to create an SDL_IOStream that is backed by dynamically allocated memory.

This supports the following properties to provide access to the memory and control over allocations: - SDL_PROP_IOSTREAM_DYNAMIC_MEMORY_POINTER: a pointer to the internal memory of the stream. This can be set to NULL to transfer ownership of the memory to the application, which should free the memory with SDL_free(). If this is done, the next operation on the stream must be SDL_CloseIO(). - SDL_PROP_IOSTREAM_DYNAMIC_CHUNKSIZE_NUMBER: memory will be allocated in multiples of this size, defaulting to 1024.

Returns
a pointer to a new SDL_IOStream structure, or NULL if it fails; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_CloseIO
SDL_ReadIO
SDL_SeekIO
SDL_TellIO
SDL_WriteIO

◆ SDL_IOFromFile()

SDL_IOStream * SDL_IOFromFile ( const char *  file,
const char *  mode 
)
extern

Use this function to create a new SDL_IOStream structure for reading from and/or writing to a named file.

The mode string is treated roughly the same as in a call to the C library's fopen(), even if SDL doesn't happen to use fopen() behind the scenes.

Available mode strings:

  • "r": Open a file for reading. The file must exist.
  • "w": Create an empty file for writing. If a file with the same name already exists its content is erased and the file is treated as a new empty file.
  • "a": Append to a file. Writing operations append data at the end of the file. The file is created if it does not exist.
  • "r+": Open a file for update both reading and writing. The file must exist.
  • "w+": Create an empty file for both reading and writing. If a file with the same name already exists its content is erased and the file is treated as a new empty file.
  • "a+": Open a file for reading and appending. All writing operations are performed at the end of the file, protecting the previous content to be overwritten. You can reposition (fseek, rewind) the internal pointer to anywhere in the file for reading, but writing operations will move it back to the end of file. The file is created if it does not exist.

NOTE: In order to open a file as a binary file, a "b" character has to be included in the mode string. This additional "b" character can either be appended at the end of the string (thus making the following compound modes: "rb", "wb", "ab", "r+b", "w+b", "a+b") or be inserted between the letter and the "+" sign for the mixed modes ("rb+", "wb+", "ab+"). Additional characters may follow the sequence, although they should have no effect. For example, "t" is sometimes appended to make explicit the file is a text file.

This function supports Unicode filenames, but they must be encoded in UTF-8 format, regardless of the underlying operating system.

As a fallback, SDL_IOFromFile() will transparently open a matching filename in an Android app's assets.

Closing the SDL_IOStream will close SDL's internal file handle.

The following properties may be set at creation time by SDL:

  • SDL_PROP_IOSTREAM_WINDOWS_HANDLE_POINTER: a pointer, that can be cast to a win32 HANDLE, that this SDL_IOStream is using to access the filesystem. If the program isn't running on Windows, or SDL used some other method to access the filesystem, this property will not be set.
  • SDL_PROP_IOSTREAM_STDIO_FILE_POINTER: a pointer, that can be cast to a stdio FILE *, that this SDL_IOStream is using to access the filesystem. If SDL used some other method to access the filesystem, this property will not be set. PLEASE NOTE that if SDL is using a different C runtime than your app, trying to use this pointer will almost certainly result in a crash! This is mostly a problem on Windows; make sure you build SDL and your app with the same compiler and settings to avoid it.
  • SDL_PROP_IOSTREAM_ANDROID_AASSET_POINTER: a pointer, that can be cast to an Android NDK AAsset *, that this SDL_IOStream is using to access the filesystem. If SDL used some other method to access the filesystem, this property will not be set.
Parameters
filea UTF-8 string representing the filename to open
modean ASCII string representing the mode to be used for opening the file.
Returns
a pointer to the SDL_IOStream structure that is created, or NULL on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_CloseIO
SDL_ReadIO
SDL_SeekIO
SDL_TellIO
SDL_WriteIO

◆ SDL_IOFromMem()

SDL_IOStream * SDL_IOFromMem ( void *  mem,
size_t  size 
)
extern

Use this function to prepare a read-write memory buffer for use with SDL_IOStream.

This function sets up an SDL_IOStream struct based on a memory area of a certain size, for both read and write access.

This memory buffer is not copied by the SDL_IOStream; the pointer you provide must remain valid until you close the stream. Closing the stream will not free the original buffer.

If you need to make sure the SDL_IOStream never writes to the memory buffer, you should use SDL_IOFromConstMem() with a read-only buffer of memory instead.

Parameters
mema pointer to a buffer to feed an SDL_IOStream stream
sizethe buffer size, in bytes
Returns
a pointer to a new SDL_IOStream structure, or NULL if it fails; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_IOFromConstMem
SDL_CloseIO
SDL_ReadIO
SDL_SeekIO
SDL_TellIO
SDL_WriteIO

◆ SDL_IOprintf()

size_t SDL_IOprintf ( SDL_IOStream context,
SDL_PRINTF_FORMAT_STRING const char *  fmt,
  ... 
)
extern

Print to an SDL_IOStream data stream.

This function does formatted printing to the stream.

Parameters
contexta pointer to an SDL_IOStream structure
fmta printf() style format string
...additional parameters matching % tokens in the fmt string, if any
Returns
the number of bytes written, or 0 on error; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_IOvprintf
SDL_WriteIO

◆ SDL_IOvprintf()

size_t SDL_IOvprintf ( SDL_IOStream context,
SDL_PRINTF_FORMAT_STRING const char *  fmt,
va_list  ap 
)
extern

Print to an SDL_IOStream data stream.

This function does formatted printing to the stream.

Parameters
contexta pointer to an SDL_IOStream structure
fmta printf() style format string
apa variable argument list
Returns
the number of bytes written, or 0 on error; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_IOprintf
SDL_WriteIO

◆ SDL_LoadFile()

void * SDL_LoadFile ( const char *  file,
size_t *  datasize 
)
extern

Load all the data from a file path.

The data is allocated with a zero byte at the end (null terminated) for convenience. This extra byte is not included in the value reported via datasize.

The data should be freed with SDL_free().

Parameters
filethe path to read all available data from
datasizeif not NULL, will store the number of bytes read
Returns
the data, or NULL if there was an error.
Since
This function is available since SDL 3.0.0.
See also
SDL_LoadFile_IO

◆ SDL_LoadFile_IO()

void * SDL_LoadFile_IO ( SDL_IOStream src,
size_t *  datasize,
SDL_bool  closeio 
)
extern

Load all the data from an SDL data stream.

The data is allocated with a zero byte at the end (null terminated) for convenience. This extra byte is not included in the value reported via datasize.

The data should be freed with SDL_free().

Parameters
srcthe SDL_IOStream to read all available data from
datasizeif not NULL, will store the number of bytes read
closeioif SDL_TRUE, calls SDL_CloseIO() on src before returning, even in the case of an error
Returns
the data, or NULL if there was an error.
Since
This function is available since SDL 3.0.0.
See also
SDL_LoadFile

◆ SDL_OpenIO()

SDL_IOStream * SDL_OpenIO ( const SDL_IOStreamInterface iface,
void *  userdata 
)
extern

Create a custom SDL_IOStream.

Applications do not need to use this function unless they are providing their own SDL_IOStream implementation. If you just need an SDL_IOStream to read/write a common data source, you should use the built-in implementations in SDL, like SDL_IOFromFile() or SDL_IOFromMem(), etc.

You must free the returned pointer with SDL_CloseIO().

Parameters
ifaceThe function pointers that implement this SDL_IOStream.
userdataThe app-controlled pointer that is passed to iface's functions when called.
Returns
a pointer to the allocated memory on success, or NULL on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_CloseIO
SDL_IOFromConstMem
SDL_IOFromFile
SDL_IOFromMem

◆ SDL_ReadIO()

size_t SDL_ReadIO ( SDL_IOStream context,
void *  ptr,
size_t  size 
)
extern

Read from a data source.

This function reads up size bytes from the data source to the area pointed at by ptr. This function may read less bytes than requested. It will return zero when the data stream is completely read, or -1 on error. For streams that support non-blocking operation, if nothing was read because it would require blocking, this function returns -2 to distinguish that this is not an error or end-of-file, and the caller can try again later.

Parameters
contexta pointer to an SDL_IOStream structure
ptra pointer to a buffer to read data into
sizethe number of bytes to read from the data source.
Returns
the number of bytes read, or 0 on end of file or other error.
Since
This function is available since SDL 3.0.0.
See also
SDL_SeekIO
SDL_WriteIO

◆ SDL_ReadS16BE()

SDL_bool SDL_ReadS16BE ( SDL_IOStream src,
Sint16 value 
)
extern

Use this function to read 16 bits of big-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadS16LE()

SDL_bool SDL_ReadS16LE ( SDL_IOStream src,
Sint16 value 
)
extern

Use this function to read 16 bits of little-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadS32BE()

SDL_bool SDL_ReadS32BE ( SDL_IOStream src,
Sint32 value 
)
extern

Use this function to read 32 bits of big-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadS32LE()

SDL_bool SDL_ReadS32LE ( SDL_IOStream src,
Sint32 value 
)
extern

Use this function to read 32 bits of little-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadS64BE()

SDL_bool SDL_ReadS64BE ( SDL_IOStream src,
Sint64 value 
)
extern

Use this function to read 64 bits of big-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadS64LE()

SDL_bool SDL_ReadS64LE ( SDL_IOStream src,
Sint64 value 
)
extern

Use this function to read 64 bits of little-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadU16BE()

SDL_bool SDL_ReadU16BE ( SDL_IOStream src,
Uint16 value 
)
extern

Use this function to read 16 bits of big-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadU16LE()

SDL_bool SDL_ReadU16LE ( SDL_IOStream src,
Uint16 value 
)
extern

Use this function to read 16 bits of little-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadU32BE()

SDL_bool SDL_ReadU32BE ( SDL_IOStream src,
Uint32 value 
)
extern

Use this function to read 32 bits of big-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadU32LE()

SDL_bool SDL_ReadU32LE ( SDL_IOStream src,
Uint32 value 
)
extern

Use this function to read 32 bits of little-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadU64BE()

SDL_bool SDL_ReadU64BE ( SDL_IOStream src,
Uint64 value 
)
extern

Use this function to read 64 bits of big-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadU64LE()

SDL_bool SDL_ReadU64LE ( SDL_IOStream src,
Uint64 value 
)
extern

Use this function to read 64 bits of little-endian data from an SDL_IOStream and return in native format.

SDL byteswaps the data only if necessary, so the data returned will be in the native byte order.

Parameters
srcthe stream from which to read data
valuea pointer filled in with the data read
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_ReadU8()

SDL_bool SDL_ReadU8 ( SDL_IOStream src,
Uint8 value 
)
extern

Use this function to read a byte from an SDL_IOStream.

Parameters
srcthe SDL_IOStream to read from
valuea pointer filled in with the data read
Returns
SDL_TRUE on success or SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_SeekIO()

Sint64 SDL_SeekIO ( SDL_IOStream context,
Sint64  offset,
int  whence 
)
extern

Seek within an SDL_IOStream data stream.

This function seeks to byte offset, relative to whence.

whence may be any of the following values:

  • SDL_IO_SEEK_SET: seek from the beginning of data
  • SDL_IO_SEEK_CUR: seek relative to current read point
  • SDL_IO_SEEK_END: seek relative to the end of data

If this stream can not seek, it will return -1.

Parameters
contexta pointer to an SDL_IOStream structure
offsetan offset in bytes, relative to whence location; can be negative
whenceany of SDL_IO_SEEK_SET, SDL_IO_SEEK_CUR, SDL_IO_SEEK_END
Returns
the final offset in the data stream after the seek or a negative error code on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_TellIO

◆ SDL_TellIO()

Sint64 SDL_TellIO ( SDL_IOStream context)
extern

Determine the current read/write offset in an SDL_IOStream data stream.

SDL_TellIO is actually a wrapper function that calls the SDL_IOStream's seek method, with an offset of 0 bytes from SDL_IO_SEEK_CUR, to simplify application development.

Parameters
contextan SDL_IOStream data stream object from which to get the current offset
Returns
the current offset in the stream, or -1 if the information can not be determined.
Since
This function is available since SDL 3.0.0.
See also
SDL_SeekIO

◆ SDL_WriteIO()

size_t SDL_WriteIO ( SDL_IOStream context,
const void *  ptr,
size_t  size 
)
extern

Write to an SDL_IOStream data stream.

This function writes exactly size bytes from the area pointed at by ptr to the stream. If this fails for any reason, it'll return less than size to demonstrate how far the write progressed. On success, it returns num.

On error, this function still attempts to write as much as possible, so it might return a positive value less than the requested write size. If the function failed to write anything and there was an actual error, it will return -1. For streams that support non-blocking operation, if nothing was written because it would require blocking, this function returns -2 to distinguish that this is not an error and the caller can try again later.

It is an error to specify a negative size, but this parameter is signed so you definitely cannot overflow the return value on a successful run with enormous amounts of data.

Parameters
contexta pointer to an SDL_IOStream structure
ptra pointer to a buffer containing data to write
sizethe number of bytes to write
Returns
the number of bytes written, which will be less than num on error; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.
See also
SDL_IOprintf
SDL_ReadIO
SDL_SeekIO

◆ SDL_WriteS16BE()

SDL_bool SDL_WriteS16BE ( SDL_IOStream dst,
Sint16  value 
)
extern

Use this function to write 16 bits in native format to an SDL_IOStream as big-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in big-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteS16LE()

SDL_bool SDL_WriteS16LE ( SDL_IOStream dst,
Sint16  value 
)
extern

Use this function to write 16 bits in native format to an SDL_IOStream as little-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in little-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteS32BE()

SDL_bool SDL_WriteS32BE ( SDL_IOStream dst,
Sint32  value 
)
extern

Use this function to write 32 bits in native format to an SDL_IOStream as big-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in big-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteS32LE()

SDL_bool SDL_WriteS32LE ( SDL_IOStream dst,
Sint32  value 
)
extern

Use this function to write 32 bits in native format to an SDL_IOStream as little-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in little-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteS64BE()

SDL_bool SDL_WriteS64BE ( SDL_IOStream dst,
Sint64  value 
)
extern

Use this function to write 64 bits in native format to an SDL_IOStream as big-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in big-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteS64LE()

SDL_bool SDL_WriteS64LE ( SDL_IOStream dst,
Sint64  value 
)
extern

Use this function to write 64 bits in native format to an SDL_IOStream as little-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in little-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteU16BE()

SDL_bool SDL_WriteU16BE ( SDL_IOStream dst,
Uint16  value 
)
extern

Use this function to write 16 bits in native format to an SDL_IOStream as big-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in big-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteU16LE()

SDL_bool SDL_WriteU16LE ( SDL_IOStream dst,
Uint16  value 
)
extern

Use this function to write 16 bits in native format to an SDL_IOStream as little-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in little-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteU32BE()

SDL_bool SDL_WriteU32BE ( SDL_IOStream dst,
Uint32  value 
)
extern

Use this function to write 32 bits in native format to an SDL_IOStream as big-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in big-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteU32LE()

SDL_bool SDL_WriteU32LE ( SDL_IOStream dst,
Uint32  value 
)
extern

Use this function to write 32 bits in native format to an SDL_IOStream as little-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in little-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteU64BE()

SDL_bool SDL_WriteU64BE ( SDL_IOStream dst,
Uint64  value 
)
extern

Use this function to write 64 bits in native format to an SDL_IOStream as big-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in big-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteU64LE()

SDL_bool SDL_WriteU64LE ( SDL_IOStream dst,
Uint64  value 
)
extern

Use this function to write 64 bits in native format to an SDL_IOStream as little-endian data.

SDL byteswaps the data only if necessary, so the application always specifies native format, and the data written will be in little-endian format.

Parameters
dstthe stream to which data will be written
valuethe data to be written, in native format
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.

◆ SDL_WriteU8()

SDL_bool SDL_WriteU8 ( SDL_IOStream dst,
Uint8  value 
)
extern

Use this function to write a byte to an SDL_IOStream.

Parameters
dstthe SDL_IOStream to write to
valuethe byte value to write
Returns
SDL_TRUE on successful write, SDL_FALSE on failure; call SDL_GetError() for more information.
Since
This function is available since SDL 3.0.0.