Class SdFatFile

SdFatFile Class

Description

Defines a class of SD FAT File.

Syntax

class SdFatFile

Members

Public Constructors
SdFatFile::SdFatFile	Constructs a SdFatFile object
SdFatFile::~SdFatFile	Destructs a SdFatFile object
Public Methods
SdFatFile::write	Write content 1 byte/bytes to file
SdFatFile::read	Read content (1 byte or bytes) from the file
SdFatFile::peek	Read 1 byte from file without move cursor
SdFatFile::available	Check if the cursor is at EOF (End-Of-File)
SdFatFile::seek	Change cursor to a specific position
SdFatFile::close	Close file
SdFatFile::cursor_pos	Indicate the current cursor position
SdFatFile::file_size	Output the size of file (DWORDs)

SdFatFile::write

Description

Write 1 byte or bytes to the file.

Syntax

virtual size_t write(uint8_t c);
virtual size_t write(const uint8_t *buf, size_t size);

Parameters

c : The character to be written.

buf : The buffer to be written.

size : The length of buffer to be written.

Returns

The function returns the number of byte count that has been successfully written to the file.

Example Code

NA.

Note

“SdFatFile.h” must be included to use the class function.

SdFatFile::read

Description

Read 1 byte or bytes from the file.

Syntax

virtual int read(void);
int read(void *buf, uint16_t nbyte);

Parameters

buf: The buffer to store the content.

nbyte: The buffer size. (Or can be regarded as the desired length to read).

Returns

The function returns a read character or the read size of the buffer.

Example Code

Example: create_folder

Note

“SdFatFile.h” must be included to use the class function.

SdFatFile::peek

Description

Read one byte from the file without moving the cursor.

Syntax

virtual int peek(void);

Parameters

NA

Returns

This function returns the read character as an integer number.

Example Code

NA

Note

“SdFatFile.h” must be included to use the class function.

SdFatFile::available

Description

Check if the cursor is at EOF.

Syntax

virtual int available(void);

Parameters

NA

Returns

The function returns 0 if the cursor is at EOF, else returns “1”.

Example Code

NA

Note

“SdFatFile.h” must be included to use the class function.

SdFatFile::seek

Description

Change cursor to a specific position.

Syntax

int seek(uint32_t pos);

Parameters

pos: The desired position.

Returns

This function returns 0 if the cursor is set a specific position successfully otherwise returns a negative value.

Example Code

NA

Note

“SdFatFile.h” must be included to use the class function.

SdFatFile::close

Description

Close file.

Syntax

int close(void);

Parameters

NA

Returns

The function returns 0 if runs successfully otherwise it returns a negative value.

Example Code

Example: create_folder

Note

“SdFatFile.h” in order to use the class function.

SdFatFile::cursor_pos

Description

Indicate the current cursor position. It is a file read/write pointer (Zeroed on file open).

Syntax

uint32_t cursor_pos (void);

Parameters

NA

Returns

This function returns a file read/write pointer. “0” on file open.

Example Code

NA

Note

“SdFatFile.h” in order to use the class function.

SdFatFile::file_size

Description

Output the size of file (DWORDs).

Syntax

uint32_t file_size (void);

Parameters

NA

Returns

This function returns a DWORD value as the file size.

Example Code

NA

Note

“SdFatFile.h” in order to use the class function.