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FPRINTF(3P)                POSIX Programmer's Manual               FPRINTF(3P)



PROLOG
       This manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may dif-
       fer (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.  Oth-
       erwise, 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, beginning and ending in its initial shift state, if any. The format is composed of zero or
       more directives: ordinary characters, which are simply copied to the output stream, and  conversion  specifica-
       tions, each of which shall result in the fetching of zero or more arguments. The results are undefined if there
       are insufficient arguments for the format. If the format is exhausted while arguments remain, the excess  argu-
       ments 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 specifications (that is, "%n$" and "*m$"), or unnum-
       bered 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 specification, 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 language-dependent radix character in the
       output string. The radix character 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 conver-
          sion  specifiers; the number of digits to appear after the radix character for the a, A, e, E, f, and F con-
          version 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 ( '.' ) followed 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 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. 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$" form of a conversion specification, a field width or pre-
       cision may be indicated by the sequence "*m$", 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 conver-
              sions the behavior is undefined. The non-monetary grouping character is used.

       -      The result of the conversion shall be left-justified within the field.  The conversion  is  right-justi-
              fied 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 necessary) to force the first digit of the result to be zero. For x or X conversion speci-
              fiers, 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 char-
              acter. 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 normally 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 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.

       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 to a long argument; that a fol-
              lowing 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 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 argu-
              ment.

       j      Specifies that a following d, i, o, u, x, or X conversion specifier applies to an intmax_t or  uintmax_t
              argument; or that a following n conversion specifier applies to a pointer to an intmax_t argument.

       z      Specifies  that  a  following d, i, o, u, x, or X conversion specifier applies to a size_t or the corre-
              sponding 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 specifier applies to a ptrdiff_t or the corre-
              sponding 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 argu-
              ment.


       If a length modifier appears with any conversion specifier other than as specified above, the behavior is unde-
       fined.

       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 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.

       o      The unsigned argument shall be converted to unsigned octal 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  con-
              verting 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 con-
              verting 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  pre-
              cision 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  miss-
              ing,  it  shall  be taken as 6; if the precision is explicitly zero and no '#' flag is present, no radix
              character 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 imple-
       mentation-defined. The F conversion specifier produces "INF", "INFINITY", or "NAN" instead  of  "inf",  "infin-
       ity", 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 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 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
              implementation-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 spec-
       ifier.

       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 spec-
       ifier.

       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 hexadec-
              imal  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 double, 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 conver-
              sion and the letters "ABCDEF" for A conversion. The A conversion 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 spec-
       ifier.

       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 converted as if by an ls conversion specifica-
       tion 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 terminating null byte. If the precision is specified, no more than  that  many  bytes
              shall be written. If the precision is not specified or is greater than the size of the array, the appli-
              cation 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 converted 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 including 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  character  if,  to equal the character sequence length given by the precision, 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  print-
              able 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 converted.

       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. Characters  gener-
       ated 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 DEC-
       IMAL_DIG, then the result should be correctly rounded. If the number of significant decimal digits is more than
       DECIMAL_DIG but the source value is exactly representable 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 execu-
       tion 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 negative 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 character 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 language-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() func-
       tion shall return a string similar to the one at the beginning of the output for the following command:


              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 getgrgid(); getgrgid() is very similar to getp-
       wuid() 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  information  and,
       using  the tm structure for values, places the date and time information into datestring. The printf() function
       then outputs datestring 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 password file by creating a link between LOCK-
       FILE 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 elements
       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 previous 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 con-
       vbuf.  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  Definitions  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, Stan-
       dard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base  Specifica-
       tions  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 Stan-
       dard,  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)