Standard C Library Functions fwprintf(3C)
NAME
fwprintf, wprintf, swprintf - print formatted wide-character
outputSYNOPSIS
#include
#include
int fwprintf(FILE *restrict stream, const wchar_t *restrict format,
...);int wprintf(const wchar_t *restrict format, ...);
int swprintf(wchar_t *restrict s, size_t n, const wchar_t *restrict format,
...);DESCRIPTION
The fwprintf() function places output on the named output stream. The wprintf() function places output on the standardoutput stream stdout. The swprintf() function places output
followed by the null wide-character in consecutive wide-
characters starting at *s; no more than n wide-characters
are written, including a terminating null wide-character,
which is always added (unless n is zero). Each of these functions converts, formats and prints itsarguments under control of the format wide-character string.
The format is composed of zero or more directives: ordinarywide-characters, which are simply copied to the output
stream and conversion specifications, each of which results in the fetching of zero or more arguments. The results areundefined if there are insufficient arguments for the for-
mat. If the format is exhausted while arguments remain, the excess arguments are evaluated but are otherwise ignored. Conversions can be applied to the nth argument after the format in the argument list, rather than to the next unusedargument. In this case, the conversion wide-character % (see
below) is replaced by the sequence %n$, where n is a decimal
integer in the range [1, NL_ARGMAX], giving the position of
the argument in the argument list. This feature provides forthe definition of format wide-character strings that select
arguments in an order appropriate to specific languages (seethe EXAMPLES section).
SunOS 5.11 Last change: 1 Nov 2003 1
Standard C Library Functions fwprintf(3C)In format wide-character strings containing the %n$ form of
conversion specifications, numbered arguments in the argu-
ment list can be referenced from the format wide-character
string as many times as required.In format wide-character strings containing the % form of
conversion specifications, each argument in the argument list is used exactly once.All forms of the fwprintf() functions allow for the inser-
tion of a language-dependent radix character in the output
string, output as a wide-character value. The radix charac-
ter is defined in the program's locale (categoryLC_NUMERIC). In the POSIX locale, or in a locale where the
radix character is not defined, the radix character defaults to a period (.).Each conversion specification is introduced by the % wide-
character or by the wide-character sequence %n$, after which
the following appear in sequence: o Zero or more flags (in any order), which modify the meaning of the conversion specification. o An optional minimum field width. If the convertedvalue has fewer wide-characters than the field
width, it will be padded with spaces by default on the left; it will be padded on the right, if theleft-adjustment flag (-), described below, is given
to the field width. The field width takes the form of an asterisk (*), described below, or a decimal integer. o An optional precision that gives the minimum number of digits to appear for the d, i, o, u, x, and X conversions; the number of digits to appear after the radix character for the a, A, e, E, f, and F conversions; the maximum number of significant digits for the g and G conversions; or the maximumnumber of wide-characters to be printed from a
string in s conversions. The precision takes the form of a period (.) followed by either an asterisk (*), described below, or an optional decimal digit string, where a null digit string is treated as 0. If a precision appears with any other conversionwide-character, the behavior is undefined.
o An optional length modifier that specifies the size of the argument.SunOS 5.11 Last change: 1 Nov 2003 2
Standard C Library Functions fwprintf(3C)o A conversion specifier wide character that indi-
cates the type of conversion to be applied. A field width, or precision, or both, may be indicated by an asterisk (*). In this case an argument of type int supplies the field width or precision. Arguments specifying field width, or precision, or both must appear in that order before the argument, if any, to be converted. A negativefield width is taken as a - flag followed by a positive
field width. A negative precision is taken as if the preci-
sion were omitted. In format wide-character strings contain-
ing the %n$ form of a conversion specification, a field
width or precision may be indicated by the sequence *m$,
where m is a decimal integer in the range [1, NL_ARGMAX]
giving the position in the argument list (after the format argument) of an integer argument containing the field width or precision, for example:wprintf(L"%1$d:%2$.*3$d:%4$.*3$d\n", hour, min, precision, sec);
The format can contain either numbered argument specifica-
tions (that is, %n$ and *m$), or unnumbered argument specif-
ications (that is, % and *), but normally not both. The only
exception to this is that %% can be mixed with the %n$ form.
The results of mixing numbered and unnumbered argumentspecifications in a format wide-character string are unde-
fined. When numbered argument specifications are used, specifying the Nth argument requires that all the leadingarguments, from the first to the (N-1)th, are specified in
the format wide-character string.
The flag wide-characters and their meanings are:
' The integer portion of the result of a decimalconversion (%i, %d, %u, %f, %F, %g, or %G) will be
formatted with thousands' grouping wide-characters.
For other conversions the behavior is undefined.The non-monetary grouping wide-character is used.
- The result of the conversion will be left-justified
within the field. The conversion will be right-
justified if this flag is not specified. + The result of a signed conversion will always beginwith a sign (+ or -). The conversion will begin
with a sign only when a negative value is convertedSunOS 5.11 Last change: 1 Nov 2003 3
Standard C Library Functions fwprintf(3C) if this flag is not specified.space If the first wide-character of a signed conversion
is not a sign or if a signed conversion results inno wide-characters, a space will be prefixed to the
result. This means that if the space and + flags both appear, the space flag will be ignored.# This flag specifies that the value is to be con-
verted to an alternative form. For o conversion, it increases the precision (if necessary) to force the first digit of the result to be 0. For x or Xconversions, a non-zero result will have 0x (or 0X)
prefixed to it. For a, A, e, E, f, F, g, or G conversions, the result will always contain a radix character, even if no digits follow it. Without this flag, a radix character appears in the result of these conversions only if a digit follows it. For g and G conversions, trailing zeros will not be removed from the result as they normally are. For other conversions, the behavior is undefined. 0 For d, i, o, u, x, X, a, A, e, E, f, F, g, and Gconversions, leading zeros (following any indica-
tion of sign or base) are used to pad to the field width; no space padding is performed. If the 0 and- flags both appear, the 0 flag will be ignored.
For d, i, o, u, x, and X conversions, if a preci-
sion is specified, the 0 flag will be ignored. Ifthe 0 and ' flags both appear, the grouping wide-
characters are inserted before zero padding. For other conversions, the behavior is undefined. The length modifiers and their meanings: hh Specifies that a following d, i, o, u, x, or X conversion specifier applies to a signed char or unsigned char argument (the argument will have been promoted according to the integer promotions, but its value shall be converted to signed char or unsigned char before printing); or that a following n conversion specifier applies to a pointer to a signed char argument.SunOS 5.11 Last change: 1 Nov 2003 4
Standard C Library Functions fwprintf(3C) h Specifies that a following d, i, o, u, x, or X conversion specifier applies to a short or unsigned short argument (the argument will have been promoted according to the integer promotions, but its value shall be converted to short or unsigned short before printing); or that a following n conversion specifier applies to a pointer to a short argument. l (ell) Specifies that a following d, i, o, u, x, or X conversion specifier applies to a long or unsigned long argument; that a following n conversion specifier applies to a pointer toa long argument; that a following c conver-
sion specifier applies to a wint_t argument;
that a following s conversion specifierapplies to a pointer to a wchar_t argument;
or has no effect on a following a, A, e, E, f, F, g, or G conversion specifier.ll (ell-ell) Specifies that a following d, i, o, u, x, or
X conversion specifier applies to a long long or unsigned long long argument; or that a following n conversion specifier applies to a pointer to a long long argument. j Specifies that a following d, i, o, u, x, or X conversion specifier applies to anintmax_t or uintmax_t argument; or that a
following n conversion specifier applies toa pointer to an intmax_t argument.
z Specifies that a following d, i, o, u, x, orX conversion specifier applies to a size_t
or the corresponding signed integer type argument; or that a following n conversion specifier applies to a pointer to a signedinteger type corresponding to size_t argu-
ment. t Specifies that a following d, i, o, u, x, or X conversion specifier applies to aptrdiff_t or the corresponding unsigned type
argument; or that a following n conversion specifier applies to a pointer to aptrdiff_t argument.
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Standard C Library Functions fwprintf(3C) L Specifies that a following a, A, e, E, f, F, g, or G conversion specifier applies to a long double argument. If a length modifier appears with any conversion specifier other than as specified above, the behavior is undefined.The conversion wide-characters and their meanings are:
d, i The int argument is converted to a signed decimal inthe style [-]dddd. The precision specifies the
minimum number of digits to appear; if the value being converted can be represented in fewer digits, it will be expanded with leading zeros. The default precision is 1. The result of converting 0 with anexplicit precision of 0 is no wide-characters.
o The unsigned int argument is converted to unsignedoctal format in the style dddd. The precision speci-
fies the minimum number of digits to appear; if the value being converted can be represented in fewer digits, it will be expanded with leading zeros. The default precision is 1. The result of converting 0with an explicit precision of 0 is no wide-
characters. u The unsigned int argument is converted to unsigned decimal format in the style dddd. The precision specifies the minimum number of digits to appear; if the value being converted can be represented in fewer digits, it will be expanded with leading zeros. The default precision is 1. The result of converting 0 with an explicit precision of 0 is nowide-characters.
x The unsigned int argument is converted to unsigned hexadecimal format in the style dddd; the letters abcdef are used. The precision specifies the minimumnumber of digits to appear; if the value being con-
verted can be represented in fewer digits, it willbe expanded with leading zeros. The default preci-
sion is 1. The result of converting 0 with an expli-
cit precision of 0 is no wide-characters.
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Standard C Library Functions fwprintf(3C)X Behaves the same as the x conversion wide-character
except that letters "ABCDEF" are used instead of "abcdef". f, F The double argument is converted to decimal notationin the style [-]ddd.ddd, where the number of digits
after the radix character (see setlocale(3C)) isequal to the precision specification. If the preci-
sion is missing it is taken as 6; if the precisionis explicitly 0 and the # flag is not specified, no
radix character appears. If a radix character appears, at least 1 digit appears before it. Theconverted value is rounded to fit the specified out-
put format according to the prevailing floating point rounding direction mode. If the conversion is not exact, an inexact exception is raised. For the f specifier, a double argument representing an infinity or NaN is converted in the style of the e conversion specifier, except that for an infinite argument, "infinity" or "Infinity" is printed when the precision is at least 8 and "inf" or "Inf" is printed otherwise. For the F specifier, a double argument representing an infinity or NaN is converted in the SUSv3 style of the E conversion specifier, except that for an infinite argument, "INFINITY" is printed when theprecision is at least 8 and or "INF" is printed oth-
erwise. e, E The double argument is converted in the style[-]d.ddde+_dd, where there is one digit before the
radix character (which is non-zero if the argument
is non-zero) and the number of digits after it is
equal to the precision; if the precision is missing,it is taken as 6; if the precision is 0 and no #
flag is present, no radix character appears. Theconverted value is rounded to fit the specified out-
put format according to the prevailing floating point rounding direction mode. If the conversion is not exact, an inexact exception is raised. The Econversion wide-character will produce a number with
E instead of e introducing the exponent. The exponent always contains at least two digits. If the value is 0, the exponent is 0. Infinity and NaN values are handled in one of the following ways:SunOS 5.11 Last change: 1 Nov 2003 7
Standard C Library Functions fwprintf(3C) SUSv3 For the e specifier, a double argument representing an infinity is printed as"[-]infinity", when the precision for the
conversion is at least 7 and as "[-]inf"
otherwise. A double argument representinga NaN is printed as "[-]nan". For the E
specifier, "INF", "INFINITY", and "NAN" are printed instead of "inf", "infinity", and "nan", respectively. Printing of the sign follows the rules described above.Default A double argument representing an infin-
ity is printed as "[-]Infinity", when the
precision for the conversion is at least7 and as "[-]Inf" otherwise. A double
argument representing a NaN is printed as"[-]NaN". Printing of the sign follows
the rules described above. g, G The double argument is converted in the style f or e (or in the style E in the case of a G conversionwide-character), with the precision specifying the
number of significant digits. If an explicit preci-
sion is 0, it is taken as 1. The style used depends on the value converted; style e (or E ) will be usedonly if the exponent resulting from such a conver-
sion is less than -4 or greater than or equal to the
precision. Trailing zeros are removed from the frac-
tional portion of the result; a radix character appears only if it is followed by a digit. A double argument representing an infinity or NaN is converted in the style of the e or E conversion specifier, except that for an infinite argument, "infinity", "INFINITY", or "Infinity" is printed when the precision is at least 8 and "inf", "INF", or "Inf" is printed otherwise.a, A A double argument representing a floating-point
number is converted in the style "[-]0xh.hhhhp+_d",
where the single hexadecimal digit preceding the radix point is 0 if the value converted is zero and 1 otherwise and the number of hexadecimal digitsafter it are equal to the precision; if the preci-
sion is missing, the number of digits printed after the radix point is 13 for the conversion of a double value, 16 for the conversion of a long double value on x86, and 28 for the conversion of a long doubleSunOS 5.11 Last change: 1 Nov 2003 8
Standard C Library Functions fwprintf(3C)value on SPARC; if the precision is zero and the '#'
flag is not specified, no decimal-point wide charac-
ter appears. The letters "abcdef" are used for aconversion and the letters "ABCDEF" for A conver-
sion. The A conversion specifier produces a number with 'X' and 'P' instead of 'x' and 'p'. The exponent always contains at least one digit, and only as many more digits as necessary to represent the decimal exponent of 2. If the value is zero, the exponent is zero. The converted valueis rounded to fit the specified output format according to the prevailing floating point rounding direction mode. If the conversion is not exact, an inexact exception is raised. A double argument representing an infinity or NaN is converted in the SUSv3 style of an e or E conversion specifier. c If no l (ell) qualifier is present, the int argumentis converted to a wide-character as if by calling
the btowc(3C) function and the resulting wide-
character is written. Otherwise the wint_t argument
is converted to wchar_t, and written.
s If no l (ell) qualifier is present, the argument must be a pointer to a character array containing a character sequence beginning in the initial shift state. Characters from the array are converted as if by repeated calls to the mbrtowc(3C) function, withthe conversion state described by an mbstate_t
object initialized to zero before the first charac-
ter is converted, and written up to (but not includ-
ing) the terminating null wide-character. If the
precision is specified, no more than that manywide-characters are written. If the precision is not
specified or is greater than the size of the array,the array must contain a null wide-character.
If an l (ell) qualifier is present, the argumentmust be a pointer to an array of type wchar_t. Wide
characters from the array are written up to (but notincluding) a terminating null wide-character. If no
precision is specified or is greater than the sizeof the array, the array must contain a null wide-
character. If a precision is specified, no more thanthat many wide-characters are written.
SunOS 5.11 Last change: 1 Nov 2003 9
Standard C Library Functions fwprintf(3C) p The argument must be a pointer to void. The value of the pointer is converted to a sequence of printablewide-characters.
n The argument must be a pointer to an integer intowhich is written the number of wide-characters writ-
ten to the output so far by this call to one of the fwprintf() functions. No argument is converted. C Same as lc. S Same as ls.% Output a % wide-character; no argument is converted.
The entire conversion specification must be %%.
If a conversion specification does not match one of the above forms, the behavior is undefined.In no case does a non-existent or small field width cause
truncation of a field; if the result of a conversion is wider than the field width, the field is simply expanded to contain the conversion result. Characters generated by fwprintf() and wprintf() are printed as if fputwc(3C) had been called.The st_ctime and st_mtime fields of the file will be marked
for update between the call to a successful execution of fwprintf() or wprintf() and the next successful completion of a call to fflush(3C) or fclose(3C) on the same stream or a call to exit(3C) or abort(3C).RETURN VALUES
Upon successful completion, these functions return thenumber of wide-characters transmitted excluding the ter-
minating null wide-character in the case of swprintf() or a
negative value if an output error was encountered. If n or more wide characters were requested to be written,swprintf() returns a negative value.
ERRORS
SunOS 5.11 Last change: 1 Nov 2003 10
Standard C Library Functions fwprintf(3C) For the conditions under which fwprintf() and wprintf() will fail and may fail, refer to fputwc(3C). In addition, all forms of fwprintf() may fail if:EILSEQ A wide-character code that does not correspond to
a valid character has been detected. EINVAL There are insufficient arguments. In addition, wprintf() and fwprintf() may fail if: ENOMEM Insufficient storage space is available.EXAMPLES
Example 1 Print Language-dependent Date and Time Format.
To print the language-independent date and time format, the
following statement could be used: wprintf(format, weekday, month, day, hour, min);For American usage, format could be a pointer to the wide-
character string:L"%s, %s %d, %d:%.2d\n"
producing the message: Sunday, July 3, 10:02 whereas for German usage, format could be a pointer to thewide-character string:
L"%1$s, %3$d. %2$s, %4$d:%5$.2d\n"
SunOS 5.11 Last change: 1 Nov 2003 11
Standard C Library Functions fwprintf(3C) producing the message: Sonntag, 3. Juli, 10:02ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Interface Stability | Committed ||_____________________________|_____________________________|
| MT-Level | MT-Safe with exceptions |
|_____________________________|_____________________________|
| Standard | See standards(5). ||_____________________________|_____________________________|
SEE ALSO
btowc(3C), fputwc(3C), fwscanf(3C), mbrtowc(3C), setlocale(3C), attributes(5), standards(5) NOTESThe fwprintf(), wprintf(), and swprintf() functions can be
used safely in multithreaded applications, as long as setlocale(3C) is not being called to change the locale.If the j length modifier is used, 32-bit applications that
were compiled using c89 on releases prior to Solaris 10 will experience undefined behavior.SunOS 5.11 Last change: 1 Nov 2003 12