FPRINTF(3P) POSIX Programmer's Manual FPRINTF(3P)
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This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding
Linux manual page for details of Linux behavior), or the interface may
not be implemented on Linux.
NAME
fprintf, printf, snprintf, sprintf - print formatted output
SYNOPSIS
#include <stdio.h>
int fprintf(FILE *restrict stream, const char *restrict format, ...);
int printf(const char *restrict format, ...);
int snprintf(char *restrict s, size_t n,
const char *restrict format, ...);
int sprintf(char *restrict s, const char *restrict format, ...);
DESCRIPTION
The fprintf() function shall place output on the named output stream.
The printf() function shall place output on the standard output stream
stdout. The sprintf() function shall place output followed by the null
byte, '\0', in consecutive bytes starting at *s; it is the user's
responsibility to ensure that enough space is available.
The snprintf() function shall be equivalent to sprintf(), with the
addition of the n argument which states the size of the buffer referred
to by s. If n is zero, nothing shall be written and s may be a null
pointer. Otherwise, output bytes beyond the n-1st shall be discarded
instead of being written to the array, and a null byte is written at
the end of the bytes actually written into the array.
If copying takes place between objects that overlap as a result of a
call to sprintf() or snprintf(), the results are undefined.
Each of these functions converts, formats, and prints its arguments
under control of the format. The format is a character string, begin-
ning and ending in its initial shift state, if any. The format is com-
posed of zero or more directives: ordinary characters, which are simply
copied to the output stream, and conversion specifications, each of
which shall result in the fetching of zero or more arguments. The
results are undefined if there are insufficient arguments for the for-
mat. If the format is exhausted while arguments remain, the excess
arguments shall be 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 unused argument. In this case,
the conversion specifier character % (see below) is replaced by the
sequence "%n$", where n is a decimal integer in the range
[1,{NL_ARGMAX}], giving the position of the argument in the argument
list. This feature provides for the definition of format strings that
select arguments in an order appropriate to specific languages (see the
EXAMPLES section).
The format can contain either numbered argument conversion specifica-
tions (that is, "%n$" and "*m$"), or unnumbered argument conversion
specifications (that is, % and * ), but not both. The only exception to
this is that %% can be mixed with the "%n$" form. The results of mixing
numbered and unnumbered argument specifications in a format string are
undefined. When numbered argument specifications are used, specifying
the Nth argument requires that all the leading arguments, from the
first to the (N-1)th, are specified in the format string.
In format strings containing the "%n$" form of conversion specifica-
tion, numbered arguments in the argument list can be referenced from
the format string as many times as required.
In format strings containing the % form of conversion specification,
each conversion specification uses the first unused argument in the
argument list.
All forms of the fprintf() functions allow for the insertion of a lan-
guage-dependent radix character in the output string. The radix charac-
ter is defined in the program's locale (category LC_NUMERIC ). In the
POSIX locale, or in a locale where the radix character is not defined,
the radix character shall default to a period ( '.' ).
Each conversion specification is introduced by the '%' character or by
the character sequence "%n$", after which the following appear in
sequence:
* Zero or more flags (in any order), which modify the meaning of the
conversion specification.
* An optional minimum field width. If the converted value has fewer
bytes than the field width, it shall be padded with spaces by
default on the left; it shall be padded on the right if the left-
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.
* An optional precision that gives the minimum number of digits to
appear for the d, i, o, u, x, and X conversion specifiers; the num-
ber of digits to appear after the radix character for the a, A, e,
E, f, and F conversion specifiers; the maximum number of significant
digits for the g and G conversion specifiers; or the maximum number
of bytes to be printed from a string in the s and S conversion
specifiers. The precision takes the form of a period ( '.' ) fol-
lowed either by an asterisk ( '*' ), described below, or an optional
decimal digit string, where a null digit string is treated as zero.
If a precision appears with any other conversion specifier, the
behavior is undefined.
* An optional length modifier that specifies the size of the argument.
* A conversion specifier character that indicates the type of conver-
sion 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. Applications shall ensure that arguments specifying field
width, or precision, or both appear in that order before the argument,
if any, to be converted. A negative field width is taken as a '-' flag
followed by a positive field width. A negative precision is taken as if
the precision were omitted. In format strings containing 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:
printf("%1$d:%2$.*3$d:%4$.*3$d\n", hour, min, precision, sec);
The flag characters and their meanings are:
' The integer portion of the result of a decimal conversion ( %i,
%d, %u, %f, %F, %g, or %G ) shall be formatted with thousands'
grouping characters. For other conversions the behavior is unde-
fined. The non-monetary grouping character is used.
- The result of the conversion shall be left-justified within the
field. The conversion is right-justified if this flag is not
specified.
+ The result of a signed conversion shall always begin with a sign
( '+' or '-' ). The conversion shall begin with a sign only when
a negative value is converted if this flag is not specified.
<space>
If the first character of a signed conversion is not a sign or
if a signed conversion results in no characters, a <space> shall
be prefixed to the result. This means that if the <space> and
'+' flags both appear, the <space> flag shall be ignored.
# Specifies that the value is to be converted to an alternative
form. For o conversion, it increases the precision (if neces-
sary) to force the first digit of the result to be zero. For x
or X conversion specifiers, a non-zero result shall have 0x (or
0X) prefixed to it. For a, A, e, E, f, F, g, and G conversion
specifiers, the result shall always contain a radix character,
even if no digits follow the radix character. Without this flag,
a radix character appears in the result of these conversions
only if a digit follows it. For g and G conversion specifiers,
trailing zeros shall not be removed from the result as they nor-
mally are. For other conversion specifiers, the behavior is
undefined.
0 For d, i, o, u, x, X, a, A, e, E, f, F, g, and G conversion
specifiers, leading zeros (following any indication 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 is
ignored. For d, i, o, u, x, and X conversion specifiers, if a
precision is specified, the '0' flag is ignored. If the '0' and
'" flags both appear, the grouping characters are inserted
before zero padding. For other conversions, the behavior is
undefined.
The length modifiers and their meanings are:
hh Specifies that a following d, i, o, u, x, or X conversion speci-
fier applies to a signed char or unsigned char argument (the
argument will have been promoted according to the integer promo-
tions, 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.
h Specifies that a following d, i, o, u, x, or X conversion speci-
fier 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 speci-
fier applies to a long or unsigned long argument; that a follow-
ing n conversion specifier applies to a pointer to a long argu-
ment; that a following c conversion specifier applies to a
wint_t argument; that a following s conversion specifier applies
to a pointer to a wchar_t argument; or has no effect on a fol-
lowing 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 speci-
fier 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 speci-
fier applies to an intmax_t or uintmax_t argument; or that a
following n conversion specifier applies to a pointer to an int-
max_t argument.
z Specifies that a following d, i, o, u, x, or X conversion speci-
fier 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 signed integer type corresponding to a
size_t argument.
t Specifies that a following d, i, o, u, x, or X conversion speci-
fier applies to a ptrdiff_t or the corresponding unsigned type
argument; or that a following n conversion specifier applies to
a pointer to a ptrdiff_t argument.
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 specifiers and their meanings are:
d, i The int argument shall be converted to a signed decimal in the
style "[-]dddd". The precision specifies the minimum number of
digits to appear; if the value being converted can be repre-
sented in fewer digits, it shall be expanded with leading zeros.
The default precision is 1. The result of converting zero with
an explicit precision of zero shall be no characters.
o The unsigned argument shall be converted to unsigned octal for-
mat 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 shall be expanded with leading
zeros. The default precision is 1. The result of converting
zero with an explicit precision of zero shall be no characters.
u The unsigned argument shall be 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 shall be expanded with leading
zeros. The default precision is 1. The result of converting
zero with an explicit precision of zero shall be no characters.
x The unsigned argument shall be converted to unsigned hexadecimal
format in the style "dddd"; the letters "abcdef" are used. The
precision specifies the minimum number of digits to appear; if
the value being converted can be represented in fewer digits, it
shall be expanded with leading zeros. The default precision is
1. The result of converting zero with an explicit precision of
zero shall be no characters.
X Equivalent to the x conversion specifier, except that letters
"ABCDEF" are used instead of "abcdef" .
f, F The double argument shall be converted to decimal notation in
the style "[-]ddd.ddd", where the number of digits after the
radix character is equal to the precision specification. If the
precision is missing, it shall be taken as 6; if the precision
is explicitly zero and no '#' flag is present, no radix charac-
ter shall appear. If a radix character appears, at least one
digit appears before it. The low-order digit shall be rounded
in an implementation-defined manner.
A double argument representing an infinity shall be converted in one of
the styles "[-]inf" or "[-]infinity" ; which style is implementation-
defined. A double argument representing a NaN shall be converted in one
of the styles "[-]nan(n-char-sequence)" or "[-]nan" ; which style, and
the meaning of any n-char-sequence, is implementation-defined. The F
conversion specifier produces "INF", "INFINITY", or "NAN" instead of
"inf", "infinity", or "nan", respectively.
e, E The double argument shall be converted in the style
"[-]d.ddde+-dd", where there is one digit before the radix char-
acter (which is non-zero if the argument is non-zero) and the
number of digits after it is equal to the precision; if the pre-
cision is missing, it shall be taken as 6; if the precision is
zero and no '#' flag is present, no radix character shall
appear. The low-order digit shall be rounded in an implementa-
tion-defined manner. The E conversion specifier shall produce a
number with 'E' instead of 'e' introducing the exponent. The
exponent shall always contain at least two digits. If the value
is zero, the exponent shall be zero.
A double argument representing an infinity or NaN shall be converted in
the style of an f or F conversion specifier.
g, G The double argument shall be converted in the style f or e (or
in the style F or E in the case of a G conversion specifier),
with the precision specifying the number of significant digits.
If an explicit precision is zero, it shall be taken as 1. The
style used depends on the value converted; style e (or E ) shall
be used only if the exponent resulting from such a conversion is
less than -4 or greater than or equal to the precision. Trailing
zeros shall be removed from the fractional portion of the
result; a radix character shall appear only if it is followed by
a digit or a '#' flag is present.
A double argument representing an infinity or NaN shall be converted in
the style of an f or F conversion specifier.
a, A A double argument representing a floating-point number shall be
converted in the style "[-]0xh.hhhhp+-d", where there is one
hexadecimal digit (which shall be non-zero if the argument is a
normalized floating-point number and is otherwise unspecified)
before the decimal-point character and the number of hexadecimal
digits after it is equal to the precision; if the precision is
missing and FLT_RADIX is a power of 2, then the precision shall
be sufficient for an exact representation of the value; if the
precision is missing and FLT_RADIX is not a power of 2, then the
precision shall be sufficient to distinguish values of type dou-
ble, except that trailing zeros may be omitted; if the precision
is zero and the '#' flag is not specified, no decimal-point
character shall appear. The letters "abcdef" shall be used for a
conversion and the letters "ABCDEF" for A conversion. The A con-
version specifier produces a number with 'X' and 'P' instead of
'x' and 'p' . The exponent shall always contain 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
shall be zero.
A double argument representing an infinity or NaN shall be converted in
the style of an f or F conversion specifier.
c The int argument shall be converted to an unsigned char, and the
resulting byte shall be written.
If an l (ell) qualifier is present, the wint_t argument shall be con-
verted as if by an ls conversion specification with no precision and an
argument that points to a two-element array of type wchar_t, the first
element of which contains the wint_t argument to the ls conversion
specification and the second element contains a null wide character.
s The argument shall be a pointer to an array of char. Bytes from
the array shall be written up to (but not including) any termi-
nating null byte. If the precision is specified, no more than
that many bytes shall be written. If the precision is not speci-
fied or is greater than the size of the array, the application
shall ensure that the array contains a null byte.
If an l (ell) qualifier is present, the argument shall be a pointer to
an array of type wchar_t. Wide characters from the array shall be con-
verted to characters (each as if by a call to the wcrtomb() function,
with the conversion state described by an mbstate_t object initialized
to zero before the first wide character is converted) up to and includ-
ing a terminating null wide character. The resulting characters shall
be written up to (but not including) the terminating null character
(byte). If no precision is specified, the application shall ensure that
the array contains a null wide character. If a precision is specified,
no more than that many characters (bytes) shall be written (including
shift sequences, if any), and the array shall contain a null wide char-
acter if, to equal the character sequence length given by the preci-
sion, the function would need to access a wide character one past the
end of the array. In no case shall a partial character be written.
p The argument shall be a pointer to void. The value of the
pointer is converted to a sequence of printable characters, in
an implementation-defined manner.
n The argument shall be a pointer to an integer into which is
written the number of bytes written to the output so far by this
call to one of the fprintf() functions. No argument is con-
verted.
C Equivalent to lc .
S Equivalent to ls .
% Print a '%' character; no argument is converted. The complete
conversion specification shall be %% .
If a conversion specification does not match one of the above forms,
the behavior is undefined. If any argument is not the correct type for
the corresponding conversion specification, the behavior is undefined.
In no case shall a nonexistent or small field width cause truncation of
a field; if the result of a conversion is wider than the field width,
the field shall be expanded to contain the conversion result. Charac-
ters generated by fprintf() and printf() are printed as if fputc() had
been called.
For the a and A conversion specifiers, if FLT_RADIX is a power of 2,
the value shall be correctly rounded to a hexadecimal floating number
with the given precision.
For a and A conversions, if FLT_RADIX is not a power of 2 and the
result is not exactly representable in the given precision, the result
should be one of the two adjacent numbers in hexadecimal floating style
with the given precision, with the extra stipulation that the error
should have a correct sign for the current rounding direction.
For the e, E, f, F, g, and G conversion specifiers, if the number of
significant decimal digits is at most DECIMAL_DIG, then the result
should be correctly rounded. If the number of significant decimal dig-
its is more than DECIMAL_DIG but the source value is exactly repre-
sentable with DECIMAL_DIG digits, then the result should be an exact
representation with trailing zeros. Otherwise, the source value is
bounded by two adjacent decimal strings L < U, both having DECIMAL_DIG
significant digits; the value of the resultant decimal string D should
satisfy L <= D <= U, with the extra stipulation that the error should
have a correct sign for the current rounding direction.
The st_ctime and st_mtime fields of the file shall be marked for update
between the call to a successful execution of fprintf() or printf() and
the next successful completion of a call to fflush() or fclose() on the
same stream or a call to exit() or abort().
RETURN VALUE
Upon successful completion, the fprintf() and printf() functions shall
return the number of bytes transmitted.
Upon successful completion, the sprintf() function shall return the
number of bytes written to s, excluding the terminating null byte.
Upon successful completion, the snprintf() function shall return the
number of bytes that would be written to s had n been sufficiently
large excluding the terminating null byte.
If an output error was encountered, these functions shall return a neg-
ative value.
If the value of n is zero on a call to snprintf(), nothing shall be
written, the number of bytes that would have been written had n been
sufficiently large excluding the terminating null shall be returned,
and s may be a null pointer.
ERRORS
For the conditions under which fprintf() and printf() fail and may
fail, refer to fputc() or fputwc().
In addition, all forms of fprintf() may fail if:
EILSEQ A wide-character code that does not correspond to a valid char-
acter has been detected.
EINVAL There are insufficient arguments.
The printf() and fprintf() functions may fail if:
ENOMEM Insufficient storage space is available.
The snprintf() function shall fail if:
EOVERFLOW
The value of n is greater than {INT_MAX} or the number of bytes
needed to hold the output excluding the terminating null is
greater than {INT_MAX}.
The following sections are informative.
EXAMPLES
Printing Language-Independent Date and Time
The following statement can be used to print date and time using a lan-
guage-independent format:
printf(format, weekday, month, day, hour, min);
For American usage, format could be a pointer to the following string:
"%s, %s %d, %d:%.2d\n"
This example would produce the following message:
Sunday, July 3, 10:02
For German usage, format could be a pointer to the following string:
"%1$s, %3$d. %2$s, %4$d:%5$.2d\n"
This definition of format would produce the following message:
Sonntag, 3. Juli, 10:02
Printing File Information
The following example prints information about the type, permissions,
and number of links of a specific file in a directory.
The first two calls to printf() use data decoded from a previous stat()
call. The user-defined strperm() function shall return a string simi-
lar to the one at the beginning of the output for the following com-
mand:
ls -l
The next call to printf() outputs the owner's name if it is found using
getpwuid(); the getpwuid() function shall return a passwd structure
from which the name of the user is extracted. If the user name is not
found, the program instead prints out the numeric value of the user ID.
The next call prints out the group name if it is found using get-
grgid(); getgrgid() is very similar to getpwuid() except that it shall
return group information based on the group number. Once again, if the
group is not found, the program prints the numeric value of the group
for the entry.
The final call to printf() prints the size of the file.
#include <stdio.h>
#include <sys/types.h>
#include <pwd.h>
#include <grp.h>
char *strperm (mode_t);
...
struct stat statbuf;
struct passwd *pwd;
struct group *grp;
...
printf("%10.10s", strperm (statbuf.st_mode));
printf("%4d", statbuf.st_nlink);
if ((pwd = getpwuid(statbuf.st_uid)) != NULL)
printf(" %-8.8s", pwd->pw_name);
else
printf(" %-8ld", (long) statbuf.st_uid);
if ((grp = getgrgid(statbuf.st_gid)) != NULL)
printf(" %-8.8s", grp->gr_name);
else
printf(" %-8ld", (long) statbuf.st_gid);
printf("%9jd", (intmax_t) statbuf.st_size);
...
Printing a Localized Date String
The following example gets a localized date string. The nl_langinfo()
function shall return the localized date string, which specifies the
order and layout of the date. The strftime() function takes this infor-
mation and, using the tm structure for values, places the date and time
information into datestring. The printf() function then outputs dat-
estring and the name of the entry.
#include <stdio.h>
#include <time.h>
#include <langinfo.h>
...
struct dirent *dp;
struct tm *tm;
char datestring[256];
...
strftime(datestring, sizeof(datestring), nl_langinfo (D_T_FMT), tm);
printf(" %s %s\n", datestring, dp->d_name);
...
Printing Error Information
The following example uses fprintf() to write error information to
standard error.
In the first group of calls, the program tries to open the password
lock file named LOCKFILE. If the file already exists, this is an error,
as indicated by the O_EXCL flag on the open() function. If the call
fails, the program assumes that someone else is updating the password
file, and the program exits.
The next group of calls saves a new password file as the current pass-
word file by creating a link between LOCKFILE and the new password file
PASSWDFILE.
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#define LOCKFILE "/etc/ptmp"
#define PASSWDFILE "/etc/passwd"
...
int pfd;
...
if ((pfd = open(LOCKFILE, O_WRONLY | O_CREAT | O_EXCL,
S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)) == -1)
{
fprintf(stderr, "Cannot open /etc/ptmp. Try again later.\n");
exit(1);
}
...
if (link(LOCKFILE,PASSWDFILE) == -1) {
fprintf(stderr, "Link error: %s\n", strerror(errno));
exit(1);
}
...
Printing Usage Information
The following example checks to make sure the program has the necessary
arguments, and uses fprintf() to print usage information if the
expected number of arguments is not present.
#include <stdio.h>
#include <stdlib.h>
...
char *Options = "hdbtl";
...
if (argc < 2) {
fprintf(stderr, "Usage: %s -%s <file\n", argv[0], Options); exit(1);
}
...
Formatting a Decimal String
The following example prints a key and data pair on stdout. Note use
of the '*' (asterisk) in the format string; this ensures the correct
number of decimal places for the element based on the number of ele-
ments requested.
#include <stdio.h>
...
long i;
char *keystr;
int elementlen, len;
...
while (len < elementlen) {
...
printf("%s Element%0*ld\n", keystr, elementlen, i);
...
}
Creating a Filename
The following example creates a filename using information from a pre-
vious getpwnam() function that returned the HOME directory of the user.
#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
...
char filename[PATH_MAX+1];
struct passwd *pw;
...
sprintf(filename, "%s/%d.out", pw->pw_dir, getpid());
...
Reporting an Event
The following example loops until an event has timed out. The pause()
function waits forever unless it receives a signal. The fprintf()
statement should never occur due to the possible return values of
pause().
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
...
while (!event_complete) {
...
if (pause() != -1 || errno != EINTR)
fprintf(stderr, "pause: unknown error: %s\n", strerror(errno));
}
...
Printing Monetary Information
The following example uses strfmon() to convert a number and store it
as a formatted monetary string named convbuf. If the first number is
printed, the program prints the format and the description; otherwise,
it just prints the number.
#include <monetary.h>
#include <stdio.h>
...
struct tblfmt {
char *format;
char *description;
};
struct tblfmt table[] = {
{ "%n", "default formatting" },
{ "%11n", "right align within an 11 character field" },
{ "%#5n", "aligned columns for values up to 99999" },
{ "%=*#5n", "specify a fill character" },
{ "%=0#5n", "fill characters do not use grouping" },
{ "%^#5n", "disable the grouping separator" },
{ "%^#5.0n", "round off to whole units" },
{ "%^#5.4n", "increase the precision" },
{ "%(#5n", "use an alternative pos/neg style" },
{ "%!(#5n", "disable the currency symbol" },
};
...
float input[3];
int i, j;
char convbuf[100];
...
strfmon(convbuf, sizeof(convbuf), table[i].format, input[j]);
if (j == 0) {
printf("%s %s %s\n", table[i].format,
convbuf, table[i].description);
}
else {
printf(" %s\n", convbuf);
}
...
Printing Wide Characters
The following example prints a series of wide characters. Suppose that
"L`@`" expands to three bytes:
wchar_t wz [3] = L"@@"; // Zero-terminated
wchar_t wn [3] = L"@@@"; // Unterminated
fprintf (stdout,"%ls", wz); // Outputs 6 bytes
fprintf (stdout,"%ls", wn); // Undefined because wn has no terminator
fprintf (stdout,"%4ls", wz); // Outputs 3 bytes
fprintf (stdout,"%4ls", wn); // Outputs 3 bytes; no terminator needed
fprintf (stdout,"%9ls", wz); // Outputs 6 bytes
fprintf (stdout,"%9ls", wn); // Outputs 9 bytes; no terminator needed
fprintf (stdout,"%10ls", wz); // Outputs 6 bytes
fprintf (stdout,"%10ls", wn); // Undefined because wn has no terminator
In the last line of the example, after processing three characters,
nine bytes have been output. The fourth character must then be examined
to determine whether it converts to one byte or more. If it converts
to more than one byte, the output is only nine bytes. Since there is no
fourth character in the array, the behavior is undefined.
APPLICATION USAGE
If the application calling fprintf() has any objects of type wint_t or
wchar_t, it must also include the <wchar.h> header to have these
objects defined.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
fputc(), fscanf(), setlocale(), strfmon(), wcrtomb(), the Base Defini-
tions volume of IEEE Std 1003.1-2001, Chapter 7, Locale, <stdio.h>,
<wchar.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online
at http://www.opengroup.org/unix/online.html .
IEEE/The Open Group 2003 FPRINTF(3P)
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