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

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() func-
       tion 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 argu-
       ment  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, 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 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 format. 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 appropri-
       ate to specific languages (see the EXAMPLES section).

       The format can contain either numbered argument conversion specifications (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 unde-
       fined. 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  argu-
       ments  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 spec-
       ification 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 specifi-
	  cation.

	* 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 number 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 preci-
	  sion	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 behav-
	  ior 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$" form of a conversion specifica-
       tion, a field width or precision may be indicated by the sequence "*m$", where m is a dec-
       imal  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 undefined. The non-monetary grouping character is used.

       -      The result of the conversion shall be left-justified within the field.  The conver-
	      sion 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  conver-
	      sion  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 conver-
	      sion, it increases the precision (if necessary) 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  speci-
	      fiers,  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  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 speci-
	      fiers, 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  speci-
	      fiers,  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 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 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 speci-
	      fier 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
	      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 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 specifier applies to
	      a ptrdiff_t or the corresponding unsigned type argument; or that a following n con-
	      version 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 con-
	      verted 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  preci-
	      sion 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 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 char-
	      acters.

       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	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 rep-
       resenting 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 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  num-
	      ber  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 unspec-
	      ified) 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  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 conversion 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 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 converted 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 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 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 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 appli-
       cation shall ensure that the array contains a null wide character. If a precision is spec-
       ified,  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 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 converted.

       C      Equivalent to lc .

       S      Equivalent to ls .

       %      Print a '%' character; no argument is converted. The complete conversion specifica-
	      tion shall be %% .

       If a conversion specification does not match one of the above forms, the behavior is unde-
       fined. If any argument is not the correct type for the corresponding conversion specifica-
       tion, 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 con-
       tain the conversion result. Characters 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 dec-
       imal digits is at most DECIMAL_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  repre-
       sentation with trailing zeros. Otherwise, the source value is bounded by two adjacent dec-
       imal 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 writ-
       ten 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()  function  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 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 information 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  LOCK-
       FILE. 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 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  '*'  (aster-
       isk)  in the format string; this ensures the correct number of decimal places for the ele-
       ment 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 for-
       ever 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 mone-
       tary 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 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, 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 orig-
       inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group			       2003				       FPRINTF(P)
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