Public Member Functions | Static Public Member Functions | Public Attributes | Friends

SdFile Class Reference

Access FAT16 and FAT32 files on SD and SDHC cards. More...

#include <SdFile.h>

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List of all members.

Public Member Functions

bool close ()
bool contiguousRange (uint32_t *bgnBlock, uint32_t *endBlock)
bool createContiguous (SdFile *dirFile, const char *path, uint32_t size)
uint32_t curCluster () const
uint32_t curPosition () const
bool dirEntry (dir_t *dir)
bool exists (const char *name)
uint32_t fileSize () const
uint32_t firstCluster () const
bool getFilename (char *name)
void getpos (fpos_t *pos)
bool isDir () const
bool isFile () const
bool isOpen () const
bool isRoot () const
bool isSubDir () const
void ls (uint8_t flags=0, uint8_t indent=0)
bool mkdir (SdFile *dir, const char *path, bool pFlag=true)
bool open (SdFile *dirFile, uint16_t index, uint16_t oflag)
bool open (SdFile *dirFile, const char *path, uint16_t oflag)
bool open (const char *path, uint16_t oflag)
bool openRoot (SdVolume *vol)
void print (unsigned long, int=DEC)
void print (unsigned char, int=BYTE)
void print (const String &)
void print (const char[])
void print (char, int=BYTE)
void print (int, int=DEC)
void print (unsigned int, int=DEC)
void print (long, int=DEC)
void print (double, int=2)
void println (unsigned long, int=DEC)
void println (double, int=2)
void println (void)
void println (int, int=DEC)
void println (long, int=DEC)
void println (unsigned int, int=DEC)
void println (unsigned char, int=BYTE)
void println (const String &s)
void println (const char[])
void println (char, int=BYTE)
bool printName ()
int16_t read ()
int16_t read (void *buf, uint16_t nbyte)
int8_t readDir (dir_t *dir)
bool remove ()
void rewind ()
bool rmdir ()
bool rmRfStar ()
 SdFile ()
bool seekCur (int32_t offset)
bool seekEnd (int32_t offset=0)
bool seekSet (uint32_t pos)
void setpos (fpos_t *pos)
bool sync ()
bool timestamp (uint8_t flag, uint16_t year, uint8_t month, uint8_t day, uint8_t hour, uint8_t minute, uint8_t second)
bool truncate (uint32_t size)
uint8_t type () const
SdVolumevolume () const
virtual void write (const uint8_t *buffer, size_t size)
void write (uint8_t b)
void write (const char *str)
int16_t write (const void *buf, uint16_t nbyte)
void write_P (PGM_P str)
void writeln_P (PGM_P str)

Static Public Member Functions

static void dateTimeCallback (void(*dateTime)(uint16_t *date, uint16_t *time))
static void dateTimeCallbackCancel ()
static void dirName (const dir_t &dir, char *name)
static void printDirName (const dir_t &dir, uint8_t width, bool printSlash=true)
static void printFatDate (uint16_t fatDate)
static void printFatTime (uint16_t fatTime)
static void printTwoDigits (uint8_t v)
static bool remove (SdFile *dirFile, const char *path)

Public Attributes

bool writeError

Friends

class SdFat

Detailed Description

Access FAT16 and FAT32 files on SD and SDHC cards.


Constructor & Destructor Documentation

SdFile::SdFile (  ) [inline]

Create an instance of SdFile.


Member Function Documentation

bool SdFile::close (  )

Close a file and force cached data and directory information to be written to the storage device.

Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include no file is open or an I/O error.

Reimplemented in fstream, ifstream, and ofstream.

bool SdFile::contiguousRange ( uint32_t *  bgnBlock,
uint32_t *  endBlock 
)

Check for contiguous file and return its raw block range.

Parameters:
[out]bgnBlockthe first block address for the file.
[out]endBlockthe last block address for the file.
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include file is not contiguous, file has zero length or an I/O error occurred.
bool SdFile::createContiguous ( SdFile dirFile,
const char *  path,
uint32_t  size 
)

Create and open a new contiguous file of a specified size.

Note:
This function only supports short DOS 8.3 names. See open() for more information.
Parameters:
[in]dirFileThe directory where the file will be created.
[in]pathA path with a valid DOS 8.3 file name.
[in]sizeThe desired file size.
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include path contains an invalid DOS 8.3 file name, the FAT volume has not been initialized, a file is already open, the file already exists, the root directory is full or an I/O error.
uint32_t SdFile::curCluster (  ) const [inline]
Returns:
The current cluster number for a file or directory.
uint32_t SdFile::curPosition (  ) const [inline]
Returns:
The current position for a file or directory.
static void SdFile::dateTimeCallback ( void(*)(uint16_t *date, uint16_t *time)  dateTime ) [inline, static]

Set the date/time callback function

Parameters:
[in]dateTimeThe user's call back function. The callback function is of the form:
 void dateTime(uint16_t* date, uint16_t* time) {
   uint16_t year;
   uint8_t month, day, hour, minute, second;

   // User gets date and time from GPS or real-time clock here

   // return date using FAT_DATE macro to format fields
   *date = FAT_DATE(year, month, day);

   // return time using FAT_TIME macro to format fields
   *time = FAT_TIME(hour, minute, second);
 }

Sets the function that is called when a file is created or when a file's directory entry is modified by sync(). All timestamps, access, creation, and modify, are set when a file is created. sync() maintains the last access date and last modify date/time.

See the timestamp() function.

static void SdFile::dateTimeCallbackCancel (  ) [inline, static]

Cancel the date/time callback function.

bool SdFile::dirEntry ( dir_t dir )

Return a file's directory entry

Parameters:
[out]dirLocation for return of the file's directory entry.
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure.
void SdFile::dirName ( const dir_t dir,
char *  name 
) [static]

Format the name field of dir into the 13 byte array name in standard 8.3 short name format.

Parameters:
[in]dirThe directory structure containing the name.
[out]nameA 13 byte char array for the formatted name.
bool SdFile::exists ( const char *  name )

Test for the existence of a file in a directory

Parameters:
[in]nameName of the file to be tested for.
Returns:
true if the file exists else false.
uint32_t SdFile::fileSize (  ) const [inline]
Returns:
The total number of bytes in a file or directory.
uint32_t SdFile::firstCluster (  ) const [inline]
Returns:
The first cluster number for a file or directory.
bool SdFile::getFilename ( char *  name )

Get a file's name

Parameters:
[out]nameAn array of 13 characters for the file's name.
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure.
void SdFile::getpos ( fpos_t pos )

get position for streams

Parameters:
[out]posstruct to receive position
bool SdFile::isDir (  ) const [inline]
Returns:
True if this is a SdFile for a directory else false.
bool SdFile::isFile (  ) const [inline]
Returns:
True if this is a SdFile for a file else false.
bool SdFile::isOpen (  ) const [inline]
Returns:
True if this is a SdFile for an open file/directory else false.
bool SdFile::isRoot (  ) const [inline]
Returns:
True if this is a SdFile for the root directory.
bool SdFile::isSubDir (  ) const [inline]
Returns:
True if this is a SdFile for a subdirectory else false.
void SdFile::ls ( uint8_t  flags = 0,
uint8_t  indent = 0 
)

List directory contents to Serial.

Parameters:
[in]flagsThe inclusive OR of

LS_DATE - Print file modification date

LS_SIZE - Print file size.

LS_R - Recursive list of subdirectories.

Parameters:
[in]indentAmount of space before file name. Used for recursive list to indicate subdirectory level.
bool SdFile::mkdir ( SdFile parent,
const char *  path,
bool  pFlag = true 
)

Make a new directory.

Parameters:
[in]parentAn open SdFat instance for the directory that will contain the new directory.
[in]pathA path with a valid 8.3 DOS name for the new directory.
[in]pFlagCreate missing parent directorys if true.
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include this SdFile is already open, parent is not a directory, path is invalid or already exists in parent.
bool SdFile::open ( SdFile dirFile,
uint16_t  index,
uint16_t  oflag 
)

Open a file by index.

Parameters:
[in]dirFileAn open SdFat instance for the directory.
[in]indexThe index of the directory entry for the file to be opened. The value for index is (directory file position)/32.
[in]oflagValues for oflag are constructed by a bitwise-inclusive OR of flags O_READ, O_WRITE, O_TRUNC, and O_SYNC.

See open() by path for definition of flags.

Returns:
true for success or false for failure.
bool SdFile::open ( SdFile dirFile,
const char *  path,
uint16_t  oflag 
)

Open a file or directory by name.

Parameters:
[in]dirFileAn open SdFat instance for the directory containing the file to be opened.
[in]pathA path with a valid 8.3 DOS name for a file to be opened.
[in]oflagValues for oflag are constructed by a bitwise-inclusive OR of flags from the following list

O_READ - Open for reading.

O_RDONLY - Same as O_READ.

O_WRITE - Open for writing.

O_WRONLY - Same as O_WRITE.

O_RDWR - Open for reading and writing.

O_APPEND - If set, the file offset shall be set to the end of the file prior to each write.

O_CREAT - If the file exists, this flag has no effect except as noted under O_EXCL below. Otherwise, the file shall be created

O_EXCL - If O_CREAT and O_EXCL are set, open() shall fail if the file exists.

O_SYNC - Call sync() after each write. This flag should not be used with write(uint8_t), write_P(PGM_P), writeln_P(PGM_P), or the Arduino Print class. These functions do character at a time writes so sync() will be called after each byte.

O_TRUNC - If the file exists and is a regular file, and the file is successfully opened and is not read only, its length shall be truncated to 0.

WARNING: A given file must not be opened by more than one SdFile object of file coruption may occur.

Note:
Directory files must be opened read only. Write and truncation is not allowed for directory files.
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include this SdFile is already open, dirFile is not a directory, path is invalid, the file does not exist or can't be opened in the access mode specified by oflag.
bool SdFile::open ( const char *  path,
uint16_t  oflag 
)

Open a file in the current working directory.

Parameters:
[in]pathA path with a valid 8.3 DOS name for a file to be opened.
[in]oflagValues for oflag are constructed by a bitwise-inclusive OR of open flags. see SdFile::open(SdFile*, const char*, uint8_t).
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure.
bool SdFile::openRoot ( SdVolume vol )

Open a volume's root directory.

Parameters:
[in]volThe FAT volume containing the root directory to be opened.
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include the SdFile is already open, the FAT volume has not been initialized or it a FAT12 volume.
void Print::print ( unsigned int  n,
int  base = DEC 
) [inherited]

Write an unsigned number to the associated device in ASCII.

Parameters:
[in]nthe number to be printed
[in]baseformat to be used
void Print::print ( const char  str[] ) [inherited]

Write a string to the associated device.

Parameters:
[in]strthe string to be printed
void Print::print ( const String &  s ) [inherited]

Write a string to the associated device.

Parameters:
[in]sthe string to be printed
void Print::print ( char  c,
int  base = BYTE 
) [inherited]

Write an signed byte to the associated device in ASCII.

Parameters:
[in]cthe byte to be printed
[in]baseformat to be used
void Print::print ( unsigned char  b,
int  base = BYTE 
) [inherited]

Write an unsigned byte to the associated device in ASCII.

Parameters:
[in]bthe byte to be printed
[in]baseformat to be used
void Print::print ( int  n,
int  base = DEC 
) [inherited]

Write an signed number to the associated device in ASCII.

Parameters:
[in]nthe number to be printed
[in]baseformat to be used
void Print::print ( long  n,
int  base = DEC 
) [inherited]

Write an signed number to the associated device in ASCII.

Parameters:
[in]nthe number to be printed
[in]baseformat to be used
void Print::print ( unsigned long  n,
int  base = DEC 
) [inherited]

Write an unsigned number to the associated device in ASCII.

Parameters:
[in]nthe number to be printed
[in]baseformat to be used
void Print::print ( double  n,
int  digits = 2 
) [inherited]

Write the decimal representation of an float or double to the associated device in ASCII.

Parameters:
[in]nthe number to be printed
[in]digitsthe digits in ftraction to be printed
void SdFile::printDirName ( const dir_t dir,
uint8_t  width,
bool  printSlash = true 
) [static]

Print the name field of a directory entry in 8.3 format to Serial.

Parameters:
[in]dirThe directory structure containing the name.
[in]widthBlank fill name if length is less than width.
[in]printSlashPrint '/' after directory names if true.
void SdFile::printFatDate ( uint16_t  fatDate ) [static]

Print a directory date field to Serial.

Format is yyyy-mm-dd.

Parameters:
[in]fatDateThe date field from a directory entry.
void SdFile::printFatTime ( uint16_t  fatTime ) [static]

Print a directory time field to Serial.

Format is hh:mm:ss.

Parameters:
[in]fatTimeThe time field from a directory entry.
void Print::println ( const char  c[] ) [inherited]

Write a string to the associated device followed by CR LF.

Parameters:
[in]cthe string to be printed
void Print::println ( char  c,
int  base = BYTE 
) [inherited]

Write an signed byte to the associated device in ASCII followed by CR LF.

Parameters:
[in]cthe byte to be printed
[in]baseformat to be used
void Print::println ( unsigned char  b,
int  base = BYTE 
) [inherited]

Write an unsigned byte to the associated device in ASCII followed by CR LF.

Parameters:
[in]bthe byte to be printed
[in]baseformat to be used
void Print::println ( unsigned int  n,
int  base = DEC 
) [inherited]

Write an unsigned number to the associated device in ASCII followed by CR LF.

Parameters:
[in]nthe number to be printed
[in]baseformat to be used
void Print::println ( unsigned long  n,
int  base = DEC 
) [inherited]

Write an unsigned number to the associated device in ASCII followed by CR LF.

Parameters:
[in]nthe number to be printed
[in]baseformat to be used
void Print::println ( double  n,
int  digits = 2 
) [inherited]

Write the decimal representation of an float or double to the associated device in ASCII followed by CR LF.

Parameters:
[in]nthe number to be printed
[in]digitsthe digits in ftraction to be printed
void Print::println ( void   ) [inherited]

Print CR LF

void Print::println ( int  n,
int  base = DEC 
) [inherited]

Write an signed number to the associated device in ASCII followed by CR LF.

Parameters:
[in]nthe number to be printed
[in]baseformat to be used
void Print::println ( const String &  s ) [inherited]

Write a string to the associated device followed by CR LF.

Parameters:
[in]sthe string to be printed
void Print::println ( long  n,
int  base = DEC 
) [inherited]

Write an signed number to the associated device in ASCII followed by CR LF.

Parameters:
[in]nthe number to be printed
[in]baseformat to be used
bool SdFile::printName (  )

Print a file's name to Serial

Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure.
void SdFile::printTwoDigits ( uint8_t  v ) [static]

Print a value as two digits to Serial.

Parameters:
[in]vValue to be printed, 0 <= v <= 99
int16_t SdFile::read (  )

Read the next byte from a file.

Returns:
For success read returns the next byte in the file as an int. If an error occurs or end of file is reached -1 is returned.
int16_t SdFile::read ( void *  buf,
uint16_t  nbyte 
)

Read data from a file starting at the current position.

Parameters:
[out]bufPointer to the location that will receive the data.
[in]nbyteMaximum number of bytes to read.
Returns:
For success read() returns the number of bytes read. A value less than nbyte, including zero, will be returned if end of file is reached. If an error occurs, read() returns -1. Possible errors include read() called before a file has been opened, corrupt file system or an I/O error occurred.
int8_t SdFile::readDir ( dir_t dir )

Read the next directory entry from a directory file.

Parameters:
[out]dirThe dir_t struct that will receive the data.
Returns:
For success readDir() returns the number of bytes read. A value of zero will be returned if end of file is reached. If an error occurs, readDir() returns -1. Possible errors include readDir() called before a directory has been opened, this is not a directory file or an I/O error occurred.
bool SdFile::remove (  )

Remove a file.

The directory entry and all data for the file are deleted.

Note:
This function should not be used to delete the 8.3 version of a file that has a long name. For example if a file has the long name "New Text Document.txt" you should not delete the 8.3 name "NEWTEX~1.TXT".
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include the file read-only, is a directory, or an I/O error occurred.
bool SdFile::remove ( SdFile dirFile,
const char *  path 
) [static]

Remove a file.

The directory entry and all data for the file are deleted.

Parameters:
[in]dirFileThe directory that contains the file.
[in]pathPath for the file to be removed.
Note:
This function should not be used to delete the 8.3 version of a file that has a long name. For example if a file has the long name "New Text Document.txt" you should not delete the 8.3 name "NEWTEX~1.TXT".
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include the file is a directory, is read only, dirFile is not a directory, path is not found or an I/O error occurred.
void SdFile::rewind (  ) [inline]

Set the file's current position to zero.

bool SdFile::rmdir (  )

Remove a directory file.

The directory file will be removed only if it is empty and is not the root directory. rmdir() follows DOS and Windows and ignores the read-only attribute for the directory.

Note:
This function should not be used to delete the 8.3 version of a directory that has a long name. For example if a directory has the long name "New folder" you should not delete the 8.3 name "NEWFOL~1".
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include the file is not a directory, is the root directory, is not empty, or an I/O error occurred.
bool SdFile::rmRfStar (  )

Recursively delete a directory and all contained files.

This is like the Unix/Linux 'rm -rf *' if called with the root directory hence the name.

Warning - This will remove all contents of the directory including subdirectories. The directory will then be removed if it is not root. The read-only attribute for files will be ignored.

Note:
This function should not be used to delete the 8.3 version of a directory that has a long name. See remove() and rmdir().
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure.
bool SdFile::seekCur ( int32_t  offset ) [inline]

Set the files position to current position + pos. See seekSet().

Parameters:
[in]offsetThe new position in bytes from the current position.
Returns:
true for success or false for failure.
bool SdFile::seekEnd ( int32_t  offset = 0 ) [inline]

Set the files position to end-of-file + offset. See seekSet().

Parameters:
[in]offsetThe new position in bytes from end-of-file.
Returns:
true for success or false for failure.
bool SdFile::seekSet ( uint32_t  pos )

Sets a file's position.

Parameters:
[in]posThe new position in bytes from the beginning of the file.
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure.
void SdFile::setpos ( fpos_t pos )

set position for streams

Parameters:
[out]posstruct with value for new position
bool SdFile::sync (  )

The sync() call causes all modified data and directory fields to be written to the storage device.

Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include a call to sync() before a file has been opened or an I/O error.
bool SdFile::timestamp ( uint8_t  flags,
uint16_t  year,
uint8_t  month,
uint8_t  day,
uint8_t  hour,
uint8_t  minute,
uint8_t  second 
)

Set a file's timestamps in its directory entry.

Parameters:
[in]flagsValues for flags are constructed by a bitwise-inclusive OR of flags from the following list

T_ACCESS - Set the file's last access date.

T_CREATE - Set the file's creation date and time.

T_WRITE - Set the file's last write/modification date and time.

Parameters:
[in]yearValid range 1980 - 2107 inclusive.
[in]monthValid range 1 - 12 inclusive.
[in]dayValid range 1 - 31 inclusive.
[in]hourValid range 0 - 23 inclusive.
[in]minuteValid range 0 - 59 inclusive.
[in]secondValid range 0 - 59 inclusive
Note:
It is possible to set an invalid date since there is no check for the number of days in a month.
Modify and access timestamps may be overwritten if a date time callback function has been set by dateTimeCallback().
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure.
bool SdFile::truncate ( uint32_t  length )

Truncate a file to a specified length. The current file position will be maintained if it is less than or equal to length otherwise it will be set to end of file.

Parameters:
[in]lengthThe desired length for the file.
Returns:
The value one, true, is returned for success and the value zero, false, is returned for failure. Reasons for failure include file is read only, file is a directory, length is greater than the current file size or an I/O error occurs.
uint8_t SdFile::type (  ) const [inline]

Type of this SdFile. You should use isFile() or isDir() instead of type() if possible.

Returns:
The file or directory type.
SdVolume* SdFile::volume (  ) const [inline]
Returns:
SdVolume that contains this file.
int16_t SdFile::write ( const void *  buf,
uint16_t  nbyte 
)

Write data to an open file.

Note:
Data is moved to the cache but may not be written to the storage device until sync() is called.
Parameters:
[in]bufPointer to the location of the data to be written.
[in]nbyteNumber of bytes to write.
Returns:
For success write() returns the number of bytes written, always nbyte. If an error occurs, write() returns -1. Possible errors include write() is called before a file has been opened, write is called for a read-only file, device is full, a corrupt file system or an I/O error.
void SdFile::write ( uint8_t  b ) [virtual]

Write a byte to a file. Required by the Arduino Print class.

Parameters:
[in]bthe byte to be written. Use SdFile::writeError to check for errors.

Implements Print.

void Print::write ( const uint8_t *  buffer,
size_t  size 
) [virtual, inherited]

default implementation: may be overridden

Parameters:
[in]bufferpointer to data
[in]sizecount of bytes to be written
void SdFile::write ( const char *  str ) [virtual]

Write a string to a file. Used by the Arduino Print class.

Parameters:
[in]strPointer to the string. Use SdFile::writeError to check for errors.

Reimplemented from Print.

void SdFile::write_P ( PGM_P  str )

Write a PROGMEM string to a file.

Parameters:
[in]strPointer to the PROGMEM string. Use SdFile::writeError to check for errors.
void SdFile::writeln_P ( PGM_P  str )

Write a PROGMEM string followed by CR/LF to a file.

Parameters:
[in]strPointer to the PROGMEM string. Use SdFile::writeError to check for errors.

Member Data Documentation

writeError is set to true if an error occurs during a write(). Set writeError to false before calling print() and/or write() and check for true after calls to print() and/or write().


The documentation for this class was generated from the following files: