C API: Unicode stdio-like API. More...

#include <stdio.h>
#include <stdarg.h>
#include "unicode/utypes.h"
#include "unicode/ucnv.h"
#include "unicode/utrans.h"
#include "unicode/unum.h"
#include "unicode/localpointer.h"

Namespaces
namespace	icu
	File coll.h.

Macros
#define	U_EOF 0xFFFF
	When an end of file is encountered, this value can be returned. More...

Typedefs
typedef struct UFILE	UFILE
	Forward declaration of a Unicode-aware file. More...

Enumerations
enum	UFileDirection { U_READ = 1 , U_WRITE = 2 , U_READWRITE =3 }
	Enum for which direction of stream a transliterator applies to. More...

Functions
U_CAPI UFILE *	u_fopen (const char filename, const char perm, const char locale, const char codepage)
	Open a UFILE. More...

U_CAPI UFILE *	u_fopen_u (const UChar filename, const char perm, const char locale, const char codepage)
	Open a UFILE with a UChar* filename A UFILE is a wrapper around a FILE* that is locale and codepage aware. More...

U_CAPI UFILE *	u_finit (FILE f, const char locale, const char *codepage)
	Open a UFILE on top of an existing FILE* stream. More...

U_CAPI UFILE *	u_fadopt (FILE f, const char locale, const char *codepage)
	Open a UFILE on top of an existing FILE* stream. More...

U_CAPI UFILE *	u_fstropen (UChar stringBuf, int32_t capacity, const char locale)
	Create a UFILE that can be used for localized formatting or parsing. More...

U_CAPI void	u_fclose (UFILE *file)
	Close a UFILE. More...

U_CAPI UBool	u_feof (UFILE *f)
	Tests if the UFILE is at the end of the file stream. More...

U_CAPI void	u_fflush (UFILE *file)
	Flush output of a UFILE. More...

U_CAPI void	u_frewind (UFILE *file)
	Rewind the file pointer to the beginning of the file. More...

U_CAPI FILE *	u_fgetfile (UFILE *f)
	Get the FILE* associated with a UFILE. More...

U_CAPI const char *	u_fgetlocale (UFILE *file)
	Get the locale whose conventions are used to format and parse output. More...

U_CAPI int32_t	u_fsetlocale (UFILE file, const char locale)
	Set the locale whose conventions will be used to format and parse output. More...

U_CAPI const char *	u_fgetcodepage (UFILE *file)
	Get the codepage in which data is written to and read from the UFILE. More...

U_CAPI int32_t	u_fsetcodepage (const char codepage, UFILE file)
	Set the codepage in which data will be written to and read from the UFILE. More...

U_CAPI UConverter *	u_fgetConverter (UFILE *f)
	Returns an alias to the converter being used for this file. More...

U_CAPI const UNumberFormat *	u_fgetNumberFormat (UFILE *f)
	Returns an alias to the number formatter being used for this file. More...

U_CAPI int32_t	u_printf (const char *patternSpecification,...)
	Write formatted data to `stdout`. More...

U_CAPI int32_t	u_fprintf (UFILE f, const char patternSpecification,...)
	Write formatted data to a UFILE. More...

U_CAPI int32_t	u_vfprintf (UFILE f, const char patternSpecification, va_list ap)
	Write formatted data to a UFILE. More...

U_CAPI int32_t	u_printf_u (const UChar *patternSpecification,...)
	Write formatted data to `stdout`. More...

U_CAPI UFILE *	u_get_stdout (void)
	Get a UFILE for `stdout`. More...

U_CAPI int32_t	u_fprintf_u (UFILE f, const UChar patternSpecification,...)
	Write formatted data to a UFILE. More...

U_CAPI int32_t	u_vfprintf_u (UFILE f, const UChar patternSpecification, va_list ap)
	Write formatted data to a UFILE. More...

U_CAPI int32_t	u_fputs (const UChar s, UFILE f)
	Write a Unicode to a UFILE. More...

U_CAPI UChar32	u_fputc (UChar32 uc, UFILE *f)
	Write a UChar to a UFILE. More...

U_CAPI int32_t	u_file_write (const UChar ustring, int32_t count, UFILE f)
	Write Unicode to a UFILE. More...

U_CAPI int32_t	u_fscanf (UFILE f, const char patternSpecification,...)
	Read formatted data from a UFILE. More...

U_CAPI int32_t	u_vfscanf (UFILE f, const char patternSpecification, va_list ap)
	Read formatted data from a UFILE. More...

U_CAPI int32_t	u_fscanf_u (UFILE f, const UChar patternSpecification,...)
	Read formatted data from a UFILE. More...

U_CAPI int32_t	u_vfscanf_u (UFILE f, const UChar patternSpecification, va_list ap)
	Read formatted data from a UFILE. More...

U_CAPI UChar *	u_fgets (UChar s, int32_t n, UFILE f)
	Read one line of text into a UChar* string from a UFILE. More...

U_CAPI UChar	u_fgetc (UFILE *f)
	Read a UChar from a UFILE. More...

U_CAPI UChar32	u_fgetcx (UFILE *f)
	Read a UChar32 from a UFILE. More...

U_CAPI UChar32	u_fungetc (UChar32 c, UFILE *f)
	Unget a UChar from a UFILE. More...

U_CAPI int32_t	u_file_read (UChar chars, int32_t count, UFILE f)
	Read Unicode from a UFILE. More...

U_CAPI UTransliterator *	u_fsettransliterator (UFILE file, UFileDirection direction, UTransliterator adopt, UErrorCode *status)
	Set a transliterator on the UFILE. More...

U_CAPI int32_t	u_sprintf (UChar buffer, const char patternSpecification,...)
	Write formatted data to a Unicode string. More...

U_CAPI int32_t	u_snprintf (UChar buffer, int32_t count, const char patternSpecification,...)
	Write formatted data to a Unicode string. More...

U_CAPI int32_t	u_vsprintf (UChar buffer, const char patternSpecification, va_list ap)
	Write formatted data to a Unicode string. More...

U_CAPI int32_t	u_vsnprintf (UChar buffer, int32_t count, const char patternSpecification, va_list ap)
	Write formatted data to a Unicode string. More...

U_CAPI int32_t	u_sprintf_u (UChar buffer, const UChar patternSpecification,...)
	Write formatted data to a Unicode string. More...

U_CAPI int32_t	u_snprintf_u (UChar buffer, int32_t count, const UChar patternSpecification,...)
	Write formatted data to a Unicode string. More...

U_CAPI int32_t	u_vsprintf_u (UChar buffer, const UChar patternSpecification, va_list ap)
	Write formatted data to a Unicode string. More...

U_CAPI int32_t	u_vsnprintf_u (UChar buffer, int32_t count, const UChar patternSpecification, va_list ap)
	Write formatted data to a Unicode string. More...

U_CAPI int32_t	u_sscanf (const UChar buffer, const char patternSpecification,...)
	Read formatted data from a Unicode string. More...

U_CAPI int32_t	u_vsscanf (const UChar buffer, const char patternSpecification, va_list ap)
	Read formatted data from a Unicode string. More...

U_CAPI int32_t	u_sscanf_u (const UChar buffer, const UChar patternSpecification,...)
	Read formatted data from a Unicode string. More...

U_CAPI int32_t	u_vsscanf_u (const UChar buffer, const UChar patternSpecification, va_list ap)
	Read formatted data from a Unicode string. More...

Detailed Description

C API: Unicode stdio-like API.

Unicode stdio-like C API

This API provides an stdio-like API wrapper around ICU's other formatting and parsing APIs. It is meant to ease the transition of adding Unicode support to a preexisting applications using stdio. The following is a small list of noticeable differences between stdio and ICU I/O's ustdio implementation.

Locale specific formatting and parsing is only done with file IO.
u_fstropen can be used to simulate file IO with strings. This is similar to the iostream API, and it allows locale specific formatting and parsing to be used.
This API provides uniform formatting and parsing behavior between platforms (unlike the standard stdio implementations found on various platforms).
This API is better suited for text data handling than binary data handling when compared to the typical stdio implementation.
You can specify a Transliterator while using the file IO.
You can specify a file's codepage separately from the default system codepage.

Formatting and Parsing Specification

General printf format:
%[format modifier][width][.precision][type modifier][format]

General scanf format:
%[*][format modifier][width][type modifier][format]

format	default printf type	default scanf type	description
E	double	float	Scientific with an uppercase exponent
e	double	float	Scientific with a lowercase exponent
G	double	float	Use E or f for best format
g	double	float	Use e or f for best format
f	double	float	Simple floating point without the exponent
X	int32_t	int32_t	ustdio special uppercase hex radix formatting
x	int32_t	int32_t	ustdio special lowercase hex radix formatting
d	int32_t	int32_t	Decimal format
i	int32_t	int32_t	Same as d
n	int32_t	int32_t	count (write the number of UTF-16 codeunits read/written)
o	int32_t	int32_t	ustdio special octal radix formatting
u	uint32_t	uint32_t	Decimal format
p	void *	void *	Prints the pointer value
s	char *	char *	Use default converter or specified converter from fopen
c	char	char	Use default converter or specified converter from fopen When width is specified for scanf, this acts like a non-NULL-terminated char * string. By default, only one char is written.
S	UChar *	UChar *	Null terminated UTF-16 string
C	UChar	UChar	16-bit Unicode code unit When width is specified for scanf, this acts like a non-NULL-terminated UChar * string By default, only one codepoint is written.
%[]		UChar *	Null terminated UTF-16 string which contains the filtered set of characters specified by the UnicodeSet
%%			Show a percent sign

Format modifiers

modifier	formats	type	comments
h	d, i, o, x	int16_t	short format
h	u	uint16_t	short format
h	c	char	(Unimplemented) Use invariant converter
h	s	char *	(Unimplemented) Use invariant converter
h	C	char	(Unimplemented) 8-bit Unicode code unit
h	S	char *	(Unimplemented) Null terminated UTF-8 string
l	d, i, o, x	int32_t	long format (no effect)
l	u	uint32_t	long format (no effect)
l	c	N/A	(Unimplemented) Reserved for future implementation
l	s	N/A	(Unimplemented) Reserved for future implementation
l	C	UChar32	(Unimplemented) 32-bit Unicode code unit
l	S	UChar32 *	(Unimplemented) Null terminated UTF-32 string
ll	d, i, o, x	int64_t	long long format
ll	u	uint64_t	(Unimplemented) long long format
%-	all	N/A	Left justify
%+	d, i, o, x, e, f, g, E, G	N/A	Always show the plus or minus sign. Needs data for plus sign.
%	d, i, o, x, e, f, g, E, G	N/A	Instead of a "+" output a blank character for positive numbers.
%#	d, i, o, x, e, f, g, E, G	N/A	Precede octal value with 0, hex with 0x and show the decimal point for floats.
%n	all	N/A	Width of input/output. num is an actual number from 0 to some large number.
%.n	e, f, g, E, F, G	N/A	Significant digits precision. num is an actual number from 0 to some large number. If * is used in printf, then the precision is passed in as an argument before the number to be formatted.

printf modifier %* int32_t Next argument after this one specifies the width

scanf modifier %* N/A This field is scanned, but not stored

If you are using this C API instead of the ustream.h API for C++, you can use one of the following u_fprintf examples to display a UnicodeString.


    UFILE *out = u_finit(stdout, NULL, NULL);
    UnicodeString string1("string 1");
    UnicodeString string2("string 2");
    u_fprintf(out, "%S\n", string1.getTerminatedBuffer());
    u_fprintf(out, "%.*S\n", string2.length(), string2.getBuffer());
    u_fclose(out);

Definition in file ustdio.h.

Macro Definition Documentation

◆ U_EOF

#define U_EOF 0xFFFF

When an end of file is encountered, this value can be returned.

See also: u_fgetc

Stable:: 3.0

Definition at line 212 of file ustdio.h.

Typedef Documentation

◆ UFILE

typedef struct UFILE UFILE

Forward declaration of a Unicode-aware file.

Stable:: 3.0

Definition at line 215 of file ustdio.h.

Enumeration Type Documentation

◆ UFileDirection

enum UFileDirection

Enum for which direction of stream a transliterator applies to.

See also: u_fsettransliterator

Stable:: ICU 3.0

Definition at line 222 of file ustdio.h.

Function Documentation

◆ u_fadopt()

U_CAPI UFILE * u_fadopt	(	FILE *	f,
		const char *	locale,
		const char *	codepage
	)

Open a UFILE on top of an existing FILE* stream.

The FILE* stream ownership is transferred to the new UFILE. It will be closed when the UFILE is closed.

Parameters

f	The FILE* which this UFILE will take ownership of.
locale	The locale whose conventions will be used to format and parse output. If this parameter is NULL, the default locale will be used.
codepage	The codepage in which data will be written to and read from the file. If this parameter is NULL, data will be written and read using the default codepage for `locale`, unless `locale` is NULL, in which case the system default codepage will be used.

Returns: A new UFILE, or NULL if an error occurred. If an error occurs the ownership of the FILE* stream remains with the caller.

Stable:: ICU 4.4

◆ u_fclose()

U_CAPI void u_fclose ( UFILE * file )

Close a UFILE.

Implies u_fflush first.

Parameters

file	The UFILE to close.

Stable:: ICU 3.0

See also: u_fflush

◆ u_feof()

U_CAPI UBool u_feof ( UFILE * f )

Tests if the UFILE is at the end of the file stream.

Parameters

f	The UFILE from which to read.

Returns: Returns true after the first read operation that attempts to read past the end of the file. It returns false if the current position is not end of file.

Stable:: ICU 3.0

◆ u_fflush()

U_CAPI void u_fflush ( UFILE * file )

Flush output of a UFILE.

Implies a flush of converter/transliterator state. (That is, a logical break is made in the output stream - for example if a different type of output is desired.) The underlying OS level file is also flushed. Note that for a stateful encoding, the converter may write additional bytes to return the stream to default state.

Parameters

file	The UFILE to flush.

Stable:: ICU 3.0

◆ u_fgetc()

U_CAPI UChar u_fgetc ( UFILE * f )

Read a UChar from a UFILE.

It is recommended that u_fgetcx used instead for proper parsing functions, but sometimes reading code units is needed instead of codepoints.

Parameters

f	The UFILE from which to read.

Returns: The UChar value read, or U+FFFF if no character was available.

Stable:: ICU 3.0

◆ u_fgetcodepage()

U_CAPI const char * u_fgetcodepage ( UFILE * file )

Get the codepage in which data is written to and read from the UFILE.

This is the same codepage passed in the preceding call to u_fsetcodepage or u_fopen.

Parameters

file	The UFILE to query.

Returns: The codepage in which data is written to and read from the UFILE, or NULL if an error occurred.

Stable:: ICU 3.0

◆ u_fgetConverter()

U_CAPI UConverter * u_fgetConverter ( UFILE * f )

Returns an alias to the converter being used for this file.

Parameters

f	The UFILE to get the value from

Returns: alias to the converter (The converter must not be modified or closed)

Stable:: ICU 3.0

◆ u_fgetcx()

U_CAPI UChar32 u_fgetcx ( UFILE * f )

Read a UChar32 from a UFILE.

Parameters

f	The UFILE from which to read.

Returns: The UChar32 value read, or U_EOF if no character was available, or U+FFFFFFFF if an ill-formed character was encountered.

See also: u_unescape()

Stable:: ICU 3.0

◆ u_fgetfile()

U_CAPI FILE * u_fgetfile ( UFILE * f )

Get the FILE* associated with a UFILE.

Parameters

f The UFILE

Returns: A FILE*, owned by the UFILE. (The FILE must not be modified or closed)

Stable:: ICU 3.0

◆ u_fgetlocale()

U_CAPI const char * u_fgetlocale ( UFILE * file )

Get the locale whose conventions are used to format and parse output.

This is the same locale passed in the preceding call tou_fsetlocale or u_fopen.

Parameters

file	The UFILE to set.

Returns: The locale whose conventions are used to format and parse output.

Stable:: ICU 3.0

◆ u_fgetNumberFormat()

U_CAPI const UNumberFormat * u_fgetNumberFormat ( UFILE * f )

Returns an alias to the number formatter being used for this file.

Parameters

f	The UFILE to get the value from

Returns: alias to the number formatter (The formatter must not be modified or closed)

Stable:: ICU 51

◆ u_fgets()

U_CAPI UChar * u_fgets	(	UChar *	s,
		int32_t	n,
		UFILE *	f
	)

Read one line of text into a UChar* string from a UFILE.

The newline at the end of the line is read into the string. The string is always null terminated

Parameters

f	The UFILE from which to read.
n	The maximum number of characters - 1 to read.
s	The UChar* to receive the read data. Characters will be stored successively in `s` until a newline or EOF is reached. A null character (U+0000) will be appended to `s`.

Returns: A pointer to s, or NULL if no characters were available.

Stable:: ICU 3.0

◆ u_file_read()

U_CAPI int32_t u_file_read	(	UChar *	chars,
		int32_t	count,
		UFILE *	f
	)

Read Unicode from a UFILE.

Bytes will be converted from the UFILE's underlying codepage, with subsequent conversion to Unicode. The data will not be NULL terminated.

Parameters

chars	A pointer to receive the Unicode data.
count	The number of Unicode characters to read.
f	The UFILE from which to read.

Returns: The number of Unicode characters read.

Stable:: ICU 3.0

◆ u_file_write()

U_CAPI int32_t u_file_write	(	const UChar *	ustring,
		int32_t	count,
		UFILE *	f
	)

Write Unicode to a UFILE.

The ustring passed in will be converted to the UFILE's underlying codepage before it is written.

Parameters

ustring	A pointer to the Unicode data to write.
count	The number of Unicode characters to write
f	The UFILE to which to write.

Returns: The number of Unicode characters written.

See also: u_fputs

Stable:: ICU 3.0

◆ u_finit()

U_CAPI UFILE * u_finit	(	FILE *	f,
		const char *	locale,
		const char *	codepage
	)

Open a UFILE on top of an existing FILE* stream.

The FILE* stream ownership remains with the caller. To have the UFILE take over ownership and responsibility for the FILE* stream, use the function u_fadopt.

Parameters

f	The FILE* to which this UFILE will attach and use.
locale	The locale whose conventions will be used to format and parse output. If this parameter is NULL, the default locale will be used.
codepage	The codepage in which data will be written to and read from the file. If this parameter is NULL, data will be written and read using the default codepage for `locale`, unless `locale` is NULL, in which case the system default codepage will be used.

Returns: A new UFILE, or NULL if an error occurred.

Stable:: ICU 3.0

◆ u_fopen()

U_CAPI UFILE * u_fopen	(	const char *	filename,
		const char *	perm,
		const char *	locale,
		const char *	codepage
	)

Open a UFILE.

A UFILE is a wrapper around a FILE* that is locale and codepage aware. That is, data written to a UFILE will be formatted using the conventions specified by that UFILE's Locale; this data will be in the character set specified by that UFILE's codepage.

Parameters

filename	The name of the file to open. Must be 0-terminated.
perm	The read/write permission for the UFILE; one of "r", "w", "rw"
locale	The locale whose conventions will be used to format and parse output. If this parameter is NULL, the default locale will be used.
codepage	The codepage in which data will be written to and read from the file. If this parameter is NULL the system default codepage will be used.

Returns: A new UFILE, or NULL if an error occurred.

Stable:: ICU 3.0

◆ u_fopen_u()

U_CAPI UFILE * u_fopen_u	(	const UChar *	filename,
		const char *	perm,
		const char *	locale,
		const char *	codepage
	)

Open a UFILE with a UChar* filename A UFILE is a wrapper around a FILE* that is locale and codepage aware.

That is, data written to a UFILE will be formatted using the conventions specified by that UFILE's Locale; this data will be in the character set specified by that UFILE's codepage.

Parameters

filename	The name of the file to open. Must be 0-terminated.
perm	The read/write permission for the UFILE; one of "r", "w", "rw"
locale	The locale whose conventions will be used to format and parse output. If this parameter is NULL, the default locale will be used.
codepage	The codepage in which data will be written to and read from the file. If this parameter is NULL the system default codepage will be used.

Returns: A new UFILE, or NULL if an error occurred.

Stable:: ICU 54

◆ u_fprintf()

U_CAPI int32_t u_fprintf	(	UFILE *	f,
		const char *	patternSpecification,
			...
	)

Write formatted data to a UFILE.

Parameters

f	The UFILE to which to write.
patternSpecification	A pattern specifying how `u_fprintf` will interpret the variable arguments received and format the data.

Returns: The number of Unicode characters written to f.

Stable:: ICU 3.0

◆ u_fprintf_u()

U_CAPI int32_t u_fprintf_u	(	UFILE *	f,
		const UChar *	patternSpecification,
			...
	)

Write formatted data to a UFILE.

Parameters

f	The UFILE to which to write.
patternSpecification	A pattern specifying how `u_fprintf` will interpret the variable arguments received and format the data.

Returns: The number of Unicode characters written to f.

Stable:: ICU 3.0

◆ u_fputc()

U_CAPI UChar32 u_fputc	(	UChar32	uc,
		UFILE *	f
	)

Write a UChar to a UFILE.

Parameters

uc	The UChar to write.
f	The UFILE to which to write.

Returns: The character written if successful, EOF otherwise.

Stable:: ICU 3.0

◆ u_fputs()

U_CAPI int32_t u_fputs	(	const UChar *	s,
		UFILE *	f
	)

Write a Unicode to a UFILE.

The null (U+0000) terminated UChar* s will be written to f, excluding the NULL terminator. A newline will be added to f.

Parameters

s	The UChar* to write.
f	The UFILE to which to write.

Returns: A non-negative number if successful, EOF otherwise.

See also: u_file_write

Stable:: ICU 3.0

◆ u_frewind()

U_CAPI void u_frewind ( UFILE * file )

Rewind the file pointer to the beginning of the file.

Parameters

file	The UFILE to rewind.

Stable:: ICU 3.0

◆ u_fscanf()

U_CAPI int32_t u_fscanf	(	UFILE *	f,
		const char *	patternSpecification,
			...
	)

Read formatted data from a UFILE.

Parameters

f	The UFILE from which to read.
patternSpecification	A pattern specifying how `u_fscanf` will interpret the variable arguments received and parse the data.

Returns: The number of items successfully converted and assigned, or EOF if an error occurred.

Stable:: ICU 3.0

◆ u_fscanf_u()

U_CAPI int32_t u_fscanf_u	(	UFILE *	f,
		const UChar *	patternSpecification,
			...
	)

Read formatted data from a UFILE.

Parameters

f	The UFILE from which to read.
patternSpecification	A pattern specifying how `u_fscanf` will interpret the variable arguments received and parse the data.

Returns: The number of items successfully converted and assigned, or EOF if an error occurred.

Stable:: ICU 3.0

◆ u_fsetcodepage()

U_CAPI int32_t u_fsetcodepage	(	const char *	codepage,
		UFILE *	file
	)

Set the codepage in which data will be written to and read from the UFILE.

All Unicode data written to the UFILE will be converted to this codepage before it is written to the underlying FILE*. It it generally a bad idea to mix codepages within a file. This should only be called right after opening the UFile, or after calling u_frewind.

Parameters

codepage	The codepage in which data will be written to and read from the file. For example `"latin-1"` or `"ibm-943"`. A value of NULL means the default codepage for the UFILE's current locale will be used.
file	The UFILE to set.

Returns: 0 if successful, otherwise a negative number.

See also: u_frewind

Stable:: ICU 3.0

◆ u_fsetlocale()

U_CAPI int32_t u_fsetlocale	(	UFILE *	file,
		const char *	locale
	)

Set the locale whose conventions will be used to format and parse output.

Parameters

locale	The locale whose conventions will be used to format and parse output.
file	The UFILE to query.

Returns: NULL if successful, otherwise a negative number.

Stable:: ICU 3.0

◆ u_fsettransliterator()

U_CAPI UTransliterator * u_fsettransliterator	(	UFILE *	file,
		UFileDirection	direction,
		UTransliterator *	adopt,
		UErrorCode *	status
	)

Set a transliterator on the UFILE.

The transliterator will be owned by the UFILE.

Parameters

file	The UFILE to set transliteration on
adopt	The UTransliterator to set. Can be NULL, which will mean that no transliteration is used.
direction	either U_READ, U_WRITE, or U_READWRITE - sets which direction the transliterator is to be applied to. If U_READWRITE, the "Read" transliteration will be in the inverse direction.
status	ICU error code.

Returns: The previously set transliterator, owned by the caller. If U_READWRITE is specified, only the WRITE transliterator is returned. In most cases, the caller should call utrans_close() on the result of this function.

Stable:: ICU 3.0

◆ u_fstropen()

U_CAPI UFILE * u_fstropen	(	UChar *	stringBuf,
		int32_t	capacity,
		const char *	locale
	)

Create a UFILE that can be used for localized formatting or parsing.

The u_sprintf and u_sscanf functions do not read or write numbers for a specific locale. The ustdio.h file functions can be used on this UFILE. The string is usable once u_fclose or u_fflush has been called on the returned UFILE.

Parameters

stringBuf	The string used for reading or writing.
capacity	The number of code units available for use in stringBuf
locale	The locale whose conventions will be used to format and parse output. If this parameter is NULL, the default locale will be used.

Returns: A new UFILE, or NULL if an error occurred.

Stable:: ICU 3.0

◆ u_fungetc()

U_CAPI UChar32 u_fungetc	(	UChar32	c,
		UFILE *	f
	)

Unget a UChar from a UFILE.

If this function is not the first to operate on f after a call to u_fgetc, the results are undefined. If this function is passed a character that was not received from the previous u_fgetc or u_fgetcx call, the results are undefined.

Parameters

c	The UChar to put back on the stream.
f	The UFILE to receive `c`.

Returns: The UChar32 value put back if successful, U_EOF otherwise.

Stable:: ICU 3.0

◆ u_get_stdout()

U_CAPI UFILE * u_get_stdout ( void )

Get a UFILE for stdout.

Returns: UFILE that writes to stdout

Stable:: ICU 49

◆ u_printf()

U_CAPI int32_t u_printf	(	const char *	patternSpecification,
			...
	)

Write formatted data to stdout.

Parameters

patternSpecification A pattern specifying how u_printf will interpret the variable arguments received and format the data.

Returns: The number of Unicode characters written to stdout

Stable:: ICU 49

◆ u_printf_u()

U_CAPI int32_t u_printf_u	(	const UChar *	patternSpecification,
			...
	)

Write formatted data to stdout.

Parameters

patternSpecification A pattern specifying how u_printf_u will interpret the variable arguments received and format the data.

Returns: The number of Unicode characters written to stdout

Stable:: ICU 49

◆ u_snprintf()

U_CAPI int32_t u_snprintf	(	UChar *	buffer,
		int32_t	count,
		const char *	patternSpecification,
			...
	)

Write formatted data to a Unicode string.

When the number of code units required to store the data exceeds count, then count code units of data are stored in buffer and a negative value is returned. When the number of code units required to store the data equals count, the string is not null terminated and count is returned.

Parameters

buffer	The Unicode String to which to write.
count	The number of code units to read.
patternSpecification	A pattern specifying how `u_sprintf` will interpret the variable arguments received and format the data.

Returns: The number of Unicode characters that would have been written to buffer had count been sufficiently large. This does not include the terminating null character.

Stable:: ICU 3.0

◆ u_snprintf_u()

U_CAPI int32_t u_snprintf_u	(	UChar *	buffer,
		int32_t	count,
		const UChar *	patternSpecification,
			...
	)

Write formatted data to a Unicode string.

When the number of code units required to store the data exceeds count, then count code units of data are stored in buffer and a negative value is returned. When the number of code units required to store the data equals count, the string is not null terminated and count is returned.

Parameters

buffer	The Unicode string to which to write.
count	The number of code units to read.
patternSpecification	A pattern specifying how `u_sprintf` will interpret the variable arguments received and format the data.

Returns: The number of Unicode characters that would have been written to buffer had count been sufficiently large.

Stable:: ICU 3.0

◆ u_sprintf()

U_CAPI int32_t u_sprintf	(	UChar *	buffer,
		const char *	patternSpecification,
			...
	)

Write formatted data to a Unicode string.

Parameters

buffer	The Unicode String to which to write.
patternSpecification	A pattern specifying how `u_sprintf` will interpret the variable arguments received and format the data.

Returns: The number of Unicode code units written to buffer. This does not include the terminating null character.

Stable:: ICU 3.0

◆ u_sprintf_u()

U_CAPI int32_t u_sprintf_u	(	UChar *	buffer,
		const UChar *	patternSpecification,
			...
	)

Write formatted data to a Unicode string.

Parameters

buffer	The Unicode string to which to write.
patternSpecification	A pattern specifying how `u_sprintf` will interpret the variable arguments received and format the data.

Returns: The number of Unicode characters written to buffer.

Stable:: ICU 3.0

◆ u_sscanf()

U_CAPI int32_t u_sscanf	(	const UChar *	buffer,
		const char *	patternSpecification,
			...
	)

Read formatted data from a Unicode string.

Parameters

buffer	The Unicode string from which to read.
patternSpecification	A pattern specifying how `u_sscanf` will interpret the variable arguments received and parse the data.

Returns: The number of items successfully converted and assigned, or EOF if an error occurred.

Stable:: ICU 3.0

◆ u_sscanf_u()

U_CAPI int32_t u_sscanf_u	(	const UChar *	buffer,
		const UChar *	patternSpecification,
			...
	)

Read formatted data from a Unicode string.

Parameters

buffer	The Unicode string from which to read.
patternSpecification	A pattern specifying how `u_sscanf` will interpret the variable arguments received and parse the data.

Returns: The number of items successfully converted and assigned, or EOF if an error occurred.

Stable:: ICU 3.0

◆ u_vfprintf()

U_CAPI int32_t u_vfprintf	(	UFILE *	f,
		const char *	patternSpecification,
		va_list	ap
	)

Write formatted data to a UFILE.

This is identical to u_fprintf, except that it will not call va_start and va_end.

Parameters

f	The UFILE to which to write.
patternSpecification	A pattern specifying how `u_fprintf` will interpret the variable arguments received and format the data.
ap	The argument list to use.

Returns: The number of Unicode characters written to f.

See also: u_fprintf

Stable:: ICU 3.0

◆ u_vfprintf_u()

U_CAPI int32_t u_vfprintf_u	(	UFILE *	f,
		const UChar *	patternSpecification,
		va_list	ap
	)

Write formatted data to a UFILE.

This is identical to u_fprintf_u, except that it will not call va_start and va_end.

Parameters

f	The UFILE to which to write.
patternSpecification	A pattern specifying how `u_fprintf` will interpret the variable arguments received and format the data.
ap	The argument list to use.

Returns: The number of Unicode characters written to f.

See also: u_fprintf_u

Stable:: ICU 3.0

◆ u_vfscanf()

U_CAPI int32_t u_vfscanf	(	UFILE *	f,
		const char *	patternSpecification,
		va_list	ap
	)

Read formatted data from a UFILE.

This is identical to u_fscanf, except that it will not call va_start and va_end.

Parameters

f	The UFILE from which to read.
patternSpecification	A pattern specifying how `u_fscanf` will interpret the variable arguments received and parse the data.
ap	The argument list to use.

Returns: The number of items successfully converted and assigned, or EOF if an error occurred.

See also: u_fscanf

Stable:: ICU 3.0

◆ u_vfscanf_u()

U_CAPI int32_t u_vfscanf_u	(	UFILE *	f,
		const UChar *	patternSpecification,
		va_list	ap
	)

Read formatted data from a UFILE.

This is identical to u_fscanf_u, except that it will not call va_start and va_end.

Parameters

f	The UFILE from which to read.
patternSpecification	A pattern specifying how `u_fscanf` will interpret the variable arguments received and parse the data.
ap	The argument list to use.

Returns: The number of items successfully converted and assigned, or EOF if an error occurred.

See also: u_fscanf_u

Stable:: ICU 3.0

◆ u_vsnprintf()

U_CAPI int32_t u_vsnprintf	(	UChar *	buffer,
		int32_t	count,
		const char *	patternSpecification,
		va_list	ap
	)

Write formatted data to a Unicode string.

This is identical to u_snprintf, except that it will not call va_start and va_end.

When the number of code units required to store the data exceeds count, then count code units of data are stored in buffer and a negative value is returned. When the number of code units required to store the data equals count, the string is not null terminated and count is returned.

Parameters

buffer	The Unicode string to which to write.
count	The number of code units to read.
patternSpecification	A pattern specifying how `u_sprintf` will interpret the variable arguments received and format the data.
ap	The argument list to use.

Returns: The number of Unicode characters that would have been written to buffer had count been sufficiently large.

See also: u_sprintf

Stable:: ICU 3.0

◆ u_vsnprintf_u()

U_CAPI int32_t u_vsnprintf_u	(	UChar *	buffer,
		int32_t	count,
		const UChar *	patternSpecification,
		va_list	ap
	)

Write formatted data to a Unicode string.

This is identical to u_snprintf_u, except that it will not call va_start and va_end. When the number of code units required to store the data exceeds count, then count code units of data are stored in buffer and a negative value is returned. When the number of code units required to store the data equals count, the string is not null terminated and count is returned.

Parameters

buffer	The Unicode string to which to write.
count	The number of code units to read.
patternSpecification	A pattern specifying how `u_sprintf` will interpret the variable arguments received and format the data.
ap	The argument list to use.

Returns: The number of Unicode characters that would have been written to f had count been sufficiently large.

See also: u_sprintf_u

Stable:: ICU 3.0

◆ u_vsprintf()

U_CAPI int32_t u_vsprintf	(	UChar *	buffer,
		const char *	patternSpecification,
		va_list	ap
	)

Write formatted data to a Unicode string.

This is identical to u_sprintf, except that it will not call va_start and va_end.

Parameters

buffer	The Unicode string to which to write.
patternSpecification	A pattern specifying how `u_sprintf` will interpret the variable arguments received and format the data.
ap	The argument list to use.

Returns: The number of Unicode characters written to buffer.

See also: u_sprintf

Stable:: ICU 3.0

◆ u_vsprintf_u()

U_CAPI int32_t u_vsprintf_u	(	UChar *	buffer,
		const UChar *	patternSpecification,
		va_list	ap
	)

Write formatted data to a Unicode string.

This is identical to u_sprintf_u, except that it will not call va_start and va_end.

Parameters

buffer	The Unicode string to which to write.
patternSpecification	A pattern specifying how `u_sprintf` will interpret the variable arguments received and format the data.
ap	The argument list to use.

Returns: The number of Unicode characters written to f.

See also: u_sprintf_u

Stable:: ICU 3.0

◆ u_vsscanf()

U_CAPI int32_t u_vsscanf	(	const UChar *	buffer,
		const char *	patternSpecification,
		va_list	ap
	)

Read formatted data from a Unicode string.

This is identical to u_sscanf, except that it will not call va_start and va_end.

Parameters

buffer	The Unicode string from which to read.
patternSpecification	A pattern specifying how `u_sscanf` will interpret the variable arguments received and parse the data.
ap	The argument list to use.

Returns: The number of items successfully converted and assigned, or EOF if an error occurred.

See also: u_sscanf

Stable:: ICU 3.0

◆ u_vsscanf_u()

U_CAPI int32_t u_vsscanf_u	(	const UChar *	buffer,
		const UChar *	patternSpecification,
		va_list	ap
	)

Read formatted data from a Unicode string.

This is identical to u_sscanf_u, except that it will not call va_start and va_end.

Parameters

buffer	The Unicode string from which to read.
patternSpecification	A pattern specifying how `u_sscanf` will interpret the variable arguments received and parse the data.
ap	The argument list to use.

Returns: The number of items successfully converted and assigned, or EOF if an error occurred.

See also: u_sscanf_u

Stable:: ICU 3.0

Namespaces

Macros

Typedefs

Enumerations

Functions

Detailed Description

Unicode stdio-like C API

Formatting and Parsing Specification

Macro Definition Documentation

◆ U_EOF

Typedef Documentation

◆ UFILE

Enumeration Type Documentation

◆ UFileDirection

Function Documentation

◆ u_fadopt()

◆ u_fclose()

◆ u_feof()

◆ u_fflush()

◆ u_fgetc()

◆ u_fgetcodepage()

◆ u_fgetConverter()

◆ u_fgetcx()

◆ u_fgetfile()

◆ u_fgetlocale()

◆ u_fgetNumberFormat()

◆ u_fgets()

◆ u_file_read()

◆ u_file_write()

◆ u_finit()

◆ u_fopen()

◆ u_fopen_u()

◆ u_fprintf()

◆ u_fprintf_u()

◆ u_fputc()

◆ u_fputs()

◆ u_frewind()

◆ u_fscanf()

◆ u_fscanf_u()

◆ u_fsetcodepage()

◆ u_fsetlocale()

◆ u_fsettransliterator()

◆ u_fstropen()

◆ u_fungetc()

◆ u_get_stdout()

◆ u_printf()

◆ u_printf_u()

◆ u_snprintf()

◆ u_snprintf_u()

◆ u_sprintf()

◆ u_sprintf_u()

◆ u_sscanf()

◆ u_sscanf_u()

◆ u_vfprintf()

◆ u_vfprintf_u()

◆ u_vfscanf()

◆ u_vfscanf_u()

◆ u_vsnprintf()

◆ u_vsnprintf_u()

◆ u_vsprintf()

◆ u_vsprintf_u()

◆ u_vsscanf()

◆ u_vsscanf_u()