istream Class Reference

Input Stream. More...

#include <istream.h>

Inheritance diagram for istream:

Collaboration diagram for istream:

Public Types
typedef unsigned int	fmtflags
typedef unsigned char	iostate
typedef int32_t	off_type
typedef uint8_t	openmode
typedef uint32_t	pos_type
enum	seekdir { beg, cur, end }
typedef uint32_t	streamsize

Public Member Functions
bool	bad () const
void	clear (iostate state=goodbit)
bool	eof () const
bool	fail () const
char	fill ()
char	fill (char c)
fmtflags	flags () const
fmtflags	flags (fmtflags fl)
streamsize	gcount () const
int	get ()
istream &	get (char &ch)
istream &	get (char *str, streamsize n, char delim= '\n')
istream &	getline (char *str, streamsize n, char delim= '\n')
bool	good () const
istream &	ignore (streamsize n=1, int delim=-1)
	operator const void * () const
bool	operator! () const
istream &	operator>> (istream &(*pf)(istream &str))
istream &	operator>> (ios_base &(*pf)(ios_base &str))
istream &	operator>> (ios &(*pf)(ios &str))
istream &	operator>> (char *str)
istream &	operator>> (char &ch)
istream &	operator>> (signed char *str)
istream &	operator>> (signed char &ch)
istream &	operator>> (unsigned char *str)
istream &	operator>> (unsigned char &ch)
istream &	operator>> (bool &arg)
istream &	operator>> (short &arg)
istream &	operator>> (unsigned short &arg)
istream &	operator>> (int &arg)
istream &	operator>> (unsigned int &arg)
istream &	operator>> (long &arg)
istream &	operator>> (unsigned long &arg)
istream &	operator>> (double &arg)
istream &	operator>> (float &arg)
istream &	operator>> (void *&arg)
int	peek ()
int	precision () const
int	precision (unsigned int n)
iostate	rdstate () const
istream &	seekg (pos_type pos)
istream &	seekg (off_type off, seekdir way)
fmtflags	setf (fmtflags fl)
fmtflags	setf (fmtflags fl, fmtflags mask)
void	setstate (iostate state)
void	skipWhite ()
pos_type	tellg ()
void	unsetf (fmtflags fl)
unsigned	width ()
unsigned	width (unsigned n)

Static Public Attributes
static const fmtflags	adjustfield = left | right | internal
static const openmode	app = 0X4
static const openmode	ate = 0X8
static const iostate	badbit = 0X01
static const fmtflags	basefield = dec | hex | oct
static const openmode	binary = 0X10
static const fmtflags	boolalpha = 0x0100
static const fmtflags	dec = 0x0008
static const iostate	eofbit = 0x02
static const iostate	failbit = 0X04
static const iostate	goodbit = 0x00
static const fmtflags	hex = 0x0010
static const openmode	in = 0X20
static const fmtflags	internal = 0x0004
static const fmtflags	left = 0x0001
static const fmtflags	oct = 0x0020
static const openmode	out = 0X40
static const fmtflags	right = 0x0002
static const fmtflags	showbase = 0x0200
static const fmtflags	showpoint = 0x0400
static const fmtflags	showpos = 0x0800
static const fmtflags	skipws = 0x1000
static const openmode	trunc = 0X80
static const fmtflags	uppercase = 0x4000

Detailed Description

Input Stream.

Member Typedef Documentation

typedef unsigned int ios_base::fmtflags

inherited

type for format flags

typedef unsigned char ios_base::iostate

inherited

typedef for iostate bitmask

typedef int32_t ios_base::off_type

inherited

type for relative seek offset

typedef uint8_t ios_base::openmode

inherited

typedef for iostream open mode

typedef uint32_t ios_base::pos_type

inherited

type for absolute seek position

typedef uint32_t ios_base::streamsize

inherited

unsigned size that can represent maximum file size. (violates spec - should be signed)

Member Enumeration Documentation

enum ios_base::seekdir

inherited

enumerated type for the direction of relative seeks

Enumerator
beg	seek relative to the beginning of the stream
cur	seek relative to the current stream position
end	seek relative to the end of the stream

Member Function Documentation

bool ios::bad ( ) const

inlineinherited

Returns

true if bad bit is set else false.

void ios::clear ( iostate  state = goodbit )

inlineinherited

Clear iostate bits.

Parameters

[in]

state

The flags you want to set after clearing all flags.

bool ios::eof ( ) const

inlineinherited

Returns

true if end of file has been reached else false.

Warning: An empty file returns false before the first read.

Moral: eof() is only useful in combination with fail(), to find out whether EOF was the cause for failure

bool ios::fail ( ) const

inlineinherited

Returns

true if any iostate bit other than eof are set else false.

char ios_base::fill ( )

inlineinherited

Returns

fill character

char ios_base::fill ( char  c )

inlineinherited

Set fill character

Parameters

[in]

c

new fill character

Returns

old fill character

fmtflags ios_base::flags ( ) const

inlineinherited

Returns

format flags

fmtflags ios_base::flags ( fmtflags  fl )

inlineinherited

set format flags

Parameters

[in]

fl

new flag

Returns

old flags

streamsize istream::gcount ( ) const

inline

Returns

The number of characters extracted by the last unformatted input function.

int istream::get

(

)

Extract a character if one is available.

Returns

The character or -1 if a failure occurs. A failure is indicated by the stream state.

istream & istream::get

(

char &

ch

)

Extract a character if one is available.

Parameters

[out]

ch

location to receive the extracted character.

Returns

always returns *this. A failure is indicated by the stream state.

istream & istream::get	(	char *	str,
		streamsize	n,
		char	delim = '\n'
	)

Extract characters.

Parameters

[out]	str	Location to receive extracted characters.
[in]	n	Size of str.
[in]	delim	Delimiter

Characters are extracted until extraction fails, n is less than 1, n-1 characters are extracted, or the next character equals delim (delim is not extracted). If no characters are extracted failbit is set. If end-of-file occurs the eofbit is set.

Returns

always returns *this. A failure is indicated by the stream state.

istream & istream::getline	(	char *	str,
		streamsize	n,
		char	delim = '\n'
	)

Extract characters

Parameters

[out]	str	Location to receive extracted characters.
[in]	n	Size of str.
[in]	delim	Delimiter

Characters are extracted until extraction fails, the next character equals delim (delim is extracted), or n-1 characters are extracted.

The failbit is set if no characters are extracted or n-1 characters are extracted. If end-of-file occurs the eofbit is set.

Returns

always returns *this. A failure is indicated by the stream state.

bool ios::good ( ) const

inlineinherited

Returns

True if no iostate flags are set else false.

istream & istream::ignore	(	streamsize	n = 1,
		int	delim = -1
	)

Extract characters and discard them.

Parameters

[in]	n	maximum number of characters to ignore.
[in]	delim	Delimiter.

Characters are extracted until extraction fails, n characters are extracted, or the next input character equals delim (the delimiter is extracted). If end-of-file occurs the eofbit is set.

Failures are indicated by the state of the stream.

Returns

*this

ios::operator const void * ( ) const

inlineinherited

Returns

null pointer if fail() is true.

bool ios::operator! ( ) const

inlineinherited

Returns

true if fail() else false.

istream& istream::operator>> ( istream &(*)(istream &str)  pf )

inline

call manipulator

Parameters

[in]

pf

function to call

Returns

the stream

istream& istream::operator>> ( ios_base &(*)(ios_base &str)  pf )

inline

call manipulator

Parameters

[in]

pf

function to call

Returns

the stream

istream& istream::operator>> ( ios &(*)(ios &str)  pf )

inline

call manipulator

Parameters

[in]

pf

function to call

Returns

the stream

istream& istream::operator>> ( char *  str )

inline

Extract a character string

Parameters

[out]

str

location to store the string.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( char &  ch )

inline

Extract a character

Parameters

[out]

ch

location to store the character.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( signed char *  str )

inline

Extract a character string

Parameters

[out]

str

location to store the string.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( signed char &  ch )

inline

Extract a character

Parameters

[out]

ch

location to store the character.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( unsigned char *  str )

inline

Extract a character string

Parameters

[out]

str

location to store the string.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( unsigned char &  ch )

inline

Extract a character

Parameters

[out]

ch

location to store the character.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( bool &  arg )

inline

Extract a value of type bool.

Parameters

[out]

arg

location to store the value.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( short &  arg )

inline

Extract a value of type short.

Parameters

[out]

arg

location to store the value.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( unsigned short &  arg )

inline

Extract a value of type unsigned short.

Parameters

[out]

arg

location to store the value.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( int &  arg )

inline

Extract a value of type int.

Parameters

[out]

arg

location to store the value.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( unsigned int &  arg )

inline

Extract a value of type unsigned int.

Parameters

[out]

arg

location to store the value.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( long &  arg )

inline

Extract a value of type long.

Parameters

[out]

arg

location to store the value.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( unsigned long &  arg )

inline

Extract a value of type unsigned long.

Parameters

[out]

arg

location to store the value.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( double &  arg )

inline

Extract a value of type double.

Parameters

[out]

arg

location to store the value.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( float &  arg )

inline

Extract a value of type float.

Parameters

[out]

arg

location to store the value.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::operator>> ( void *&  arg )

inline

Extract a value of type void*.

Parameters

[out]

arg

location to store the value.

Returns

Is always *this. Failure is indicated by the state of *this.

int istream::peek

(

)

Return the next available character without consuming it.

Returns

The character if the stream state is good else -1;

int ios_base::precision ( ) const

inlineinherited

Returns

precision

int ios_base::precision ( unsigned int  n )

inlineinherited

set precision

Parameters

[in]

n

new precision

Returns

old precision

iostate ios::rdstate ( ) const

inlineinherited

Returns

The iostate flags for this file.

istream& istream::seekg ( pos_type  pos )

inline

Set the stream position

Parameters

[in]

pos

The absolute position in which to move the read pointer.

Returns

Is always *this. Failure is indicated by the state of *this.

istream& istream::seekg ( off_type  off, seekdir  way  )

inline

Set the stream position.

Parameters

[in]	off	An offset to move the read pointer relative to way. off is a signed 32-bit int so the offset is limited to +- 2GB.
[in]	way	One of ios::beg, ios::cur, or ios::end.

Returns

Is always *this. Failure is indicated by the state of *this.

fmtflags ios_base::setf ( fmtflags  fl )

inlineinherited

set format flags

Parameters

[in]

fl

new flags to be or'ed in

Returns

old flags

fmtflags ios_base::setf ( fmtflags  fl, fmtflags  mask  )

inlineinherited

modify format flags

Parameters

[in]	mask	flags to be removed
[in]	fl	flags to be set after mask bits have been cleared

Returns

old flags

void ios::setstate ( iostate  state )

inlineinherited

Set iostate bits.

Parameters

[in]

state

Bitts to set.

void istream::skipWhite

(

)

used to implement ws()

pos_type istream::tellg ( )

inline

Returns

the stream position

void ios_base::unsetf ( fmtflags  fl )

inlineinherited

clear format flags

Parameters

[in]

fl

flags to be cleared

Returns

old flags

unsigned ios_base::width ( )

inlineinherited

Returns

width

unsigned ios_base::width ( unsigned  n )

inlineinherited

set width

Parameters

[in]

n

new width

Returns

old width

Member Data Documentation

const fmtflags ios_base::adjustfield = left | right | internal

staticinherited

mask for adjustfield

const openmode ios_base::app = 0X4

staticinherited

seek to end before each write

const openmode ios_base::ate = 0X8

staticinherited

open and seek to end immediately after opening

const iostate ios_base::badbit = 0X01

staticinherited

iostate bad bit for a nonrecoverable error.

const fmtflags ios_base::basefield = dec | hex | oct

staticinherited

mask for basefield

const openmode ios_base::binary = 0X10

staticinherited

perform input and output in binary mode (as opposed to text mode)

const fmtflags ios_base::boolalpha = 0x0100

staticinherited

use strings true/false for bool

const fmtflags ios_base::dec = 0x0008

staticinherited

base 10 flag

const iostate ios_base::eofbit = 0x02

staticinherited

iostate bit for end of file reached

const iostate ios_base::failbit = 0X04

staticinherited

iostate fail bit for nonfatal error

const iostate ios_base::goodbit = 0x00

staticinherited

iostate for no flags

const fmtflags ios_base::hex = 0x0010

staticinherited

base 16 flag

const openmode ios_base::in = 0X20

staticinherited

open for input

const fmtflags ios_base::internal = 0x0004

staticinherited

fill between sign/base prefix and number

const fmtflags ios_base::left = 0x0001

staticinherited

left adjust fields

const fmtflags ios_base::oct = 0x0020

staticinherited

base 8 flag

const openmode ios_base::out = 0X40

staticinherited

open for output

const fmtflags ios_base::right = 0x0002

staticinherited

right adjust fields

const fmtflags ios_base::showbase = 0x0200

staticinherited

use prefix 0X for hex and 0 for oct

const fmtflags ios_base::showpoint = 0x0400

staticinherited

always show '.' for floating numbers

const fmtflags ios_base::showpos = 0x0800

staticinherited

show + sign for nonnegative numbers

const fmtflags ios_base::skipws = 0x1000

staticinherited

skip initial white space

const openmode ios_base::trunc = 0X80

staticinherited

truncate an existing stream when opening

const fmtflags ios_base::uppercase = 0x4000

staticinherited

use uppercase letters in number representations

---

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

• Arduino/libraries/SdFat/src/FatLib/istream.h
• Arduino/libraries/SdFat/src/FatLib/istream.cpp