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printf(3UCB)	   SunOS/BSD Compatibility Library Functions	  printf(3UCB)

NAME
       printf,	fprintf, sprintf, vprintf, vfprintf, vsprintf -	formatted out-
       put conversion

SYNOPSIS
       /usr/ucb/cc [flag ...] file ...
       #include	<stdio.h>

       int printf( format,  ...);
       const char *format;

       int fprintf( stream,  format,  va_list);
       FILE *stream;
       char *format;
       va_dcl;

       char *sprintf( s,  format,  va_list);
       char *s,	*format;
       va_dcl;

       int vprintf(format, ap);
       char *format;
       va_list ap;

       int vfprintf( stream,  format,  ap);
       FILE *stream;
       char *format;
       va_list ap;

       char *vsprintf( s,  format,  ap);
       char *s,	*format;
       va_list ap;

DESCRIPTION
       printf()	places output on the standard output stream stdout.  fprintf()
       places  output  on  the named output stream. sprintf() places "output,"
       followed	by the NULL character (\0), in consecutive bytes  starting  at
       *s;  it	is  the	user's responsibility to ensure	that enough storage is
       available.

       vprintf(),  vfprintf(),	and  vsprintf()	 are  the  same	 as  printf(),
       fprintf(),  and	sprintf()  respectively,  except that instead of being
       called with a variable number of	arguments, they	are called with	an ar-
       gument list as defined by varargs(3HEAD).

       Each  of	 these	functions converts, formats, and prints	its args under
       control of the format. The format is a character	string which  contains
       two  types of objects: plain characters,	which are simply copied	to the
       output stream, and conversion specifications, each of which causes con-
       version and printing of zero or more args. The results are undefined if
       there are insufficient args for the format. If the format is  exhausted
       while args remain, the excess args are simply ignored.

       Each  conversion	 specification is introduced by	the character %. After
       the %, the following appear in sequence:

	  o  Zero or more flags, which modify the meaning  of  the  conversion
	     specification.

	  o  An	 optional  decimal  digit  string  specifying  a minimum field
	     width. If the converted value has fewer characters	than the field
	     width,  it	 will be padded	on the left (or	right, if the left-ad-
	     justment flag `-',	described below, has been given) to the	 field
	     width.  The  padding  is with blanks unless the field width digit
	     string starts with	a zero,	in which case the padding is with  ze-
	     ros.

	  o  A precision that gives the	minimum	number of digits to appear for
	     the d, i, o, u, x,	or X conversions, the number of	digits to  ap-
	     pear after	the decimal point for the e, E,	and f conversions, the
	     maximum number of significant digits for the g and	G  conversion,
	     or	 the  maximum number of	characters to be printed from a	string
	     in	s conversion. The precision takes the form  of	a  period  (.)
	     followed  by  a  decimal  digit  string;  a  NULL digit string is
	     treated as	zero. Padding specified	by the precision overrides the
	     padding specified by the field width.

	  o  An	optional l (ell) specifying that a following d,	i, o, u, x, or
	     X conversion character applies to a long integer arg. An l	before
	     any other conversion character is ignored.

	  o  A character that indicates	the type of conversion to be applied.

       A  field	width or precision or both may be indicated by an asterisk (*)
       instead of a digit string. In this case,	an integer  arg	 supplies  the
       field  width  or	 precision.  The arg that is actually converted	is not
       fetched until the conversion letter is seen,  so	 the  args  specifying
       field width or precision	must appear before the arg (if any) to be con-
       verted. A negative field	width argument is taken	as a `-' flag followed
       by  a  positive	field width. If	the precision argument is negative, it
       will be changed to zero.

       The flag	characters and their meanings are:

	      -	    The	result of the conversion will be left-justified	within
		    the	field.

	      +	    The	result of a signed conversion will always begin	with a
		    sign (+ or -).

	      blank If the first character of a	signed	conversion  is	not  a
		    sign, a blank will be prefixed to the result. This implies
		    that if the	blank and + flags both appear, the blank  flag
		    will be ignored.

	      #	    This  flag	specifies that the value is to be converted to
		    an "alternate form." For c,	d, i, s,  and  u  conversions,
		    the	flag has no effect. For	o conversion, it increases the
		    precision to force the first digit of the result to	 be  a
		    zero.  For	x or X conversion, a non-zero result will have
		    0x or 0X prefixed to it. For e, E, f,  g,  and  G  conver-
		    sions,  the	 result	 will  always contain a	decimal	point,
		    even if no digits follow the point	(normally,  a  decimal
		    point appears in the result	of these conversions only if a
		    digit follows it). For g and G conversions,	 trailing  ze-
		    roes  will not be removed from the result (which they nor-
		    mally are).

       The conversion characters and their meanings are:

	      d,i,o,u, x,X
		    The	integer	arg is converted to signed decimal (d  or  i),
		    unsigned  octal  (o),  unsigned  decimal  (u), or unsigned
		    hexadecimal	notation (x and	X), respectively; the  letters
		    abcdef  are	 used  for x conversion	and the	letters	ABCDEF
		    for	X conversion. The precision specifies the minimum num-
		    ber	 of digits to appear; if the value being converted can
		    be represented in fewer digits, it will be	expanded  with
		    leading  zeroes.  (For  compatibility with older versions,
		    padding with leading zeroes	may alternatively be specified
		    by prepending a zero to the	field width. This does not im-
		    ply	an octal value for the field width.) The default  pre-
		    cision  is 1. The result of	converting a zero value	with a
		    precision of zero is a NULL	string.

	      f	    The	float or double	arg is converted to  decimal  notation
		    in	the  style [-]ddd.ddd where the	number of digits after
		    the	decimal	point is equal to the precision	specification.
		    If	the  precision	is missing, 6 digits are given;	if the
		    precision is explicitly 0, no digits and no	decimal	 point
		    are	printed.

	      e,E   The	 float	or  double  arg	 is  converted	in  the	 style
		    [-]d.ddde+-ddd, where there	is one digit before the	 deci-
		    mal	 point	and  the number	of digits after	it is equal to
		    the	precision; when	the precision is missing, 6 digits are
		    produced;  if  the precision is zero, no decimal point ap-
		    pears. The E format	code will produce a number with	E  in-
		    stead  of  e introducing the exponent. The exponent	always
		    contains at	least two digits.

	      g,G   The	float or double	arg is printed in style	f or e (or  in
		    style  E  in the case of a G format	code), with the	preci-
		    sion specifying the	 number	 of  significant  digits.  The
		    style  used	 depends  on the value converted: style	e or E
		    will be used only if the exponent resulting	from the  con-
		    version  is	 less  than  -4	or greater than	the precision.
		    Trailing zeroes are	removed	from  the  result;  a  decimal
		    point appears only if it is	followed by a digit.

       The  e, E f, g, and G formats print IEEE	indeterminate values (infinity
       or not-a-number)	as "Infinity" or "NaN" respectively.

	      c	    The	character arg is printed.

	      s	    The	arg is taken to	be a string  (character	 pointer)  and
		    characters	from the string	are printed until a NULL char-
		    acter (\0) is encountered or until the number  of  charac-
		    ters  indicated by the precision specification is reached.
		    If the precision is	missing, it is taken to	 be  infinite,
		    so	all  characters	 up  to	 the  first NULL character are
		    printed. A NULL value for arg  will	 yield	undefined  re-
		    sults.

	      %	    Print a %; no argument is converted.

       In no case does a non-existent or small field width cause truncation of
       a field;	if the result of a conversion is wider than the	 field	width,
       the  field is simply expanded to	contain	the conversion result. Padding
       takes place only	if the specified field width exceeds the actual	width.
       Characters  generated  by  printf()  and	 fprintf()  are	 printed as if
       putc(3C)	had been called.

RETURN VALUES
       Upon success, printf() and fprintf() return the	number	of  characters
       transmitted, excluding the null character. vprintf() and	vfprintf() re-
       turn the	number of characters transmitted. sprintf() and	vsprintf() al-
       ways  return  s.	If an output error is encountered, printf(), fprint(),
       vprintf(), and vfprintf() return	EOF.

EXAMPLES
       Example 1: Examples of the printf Command To Print a Date and Time

       To print	a date and time	in the form "Sunday,  July  3,	10:02,"	 where
       weekday and month are pointers to NULL-terminated strings:

       printf("%s, %s %i, %d:%.2d", weekday, month, day, hour, min);

       Example	2:  Examples  of  the  printf Command To Print to Five Decimal
       Places

       To print	to five	decimal	places:

       printf("pi = %.5f", 4 * atan(1. 0));

SEE ALSO
       econvert(3C), putc(3C), scanf(3C), vprintf(3C), varargs(3HEAD)

NOTES
       Use of these interfaces should be restricted to only applications writ-
       ten  on	BSD platforms.	Use of these interfaces	with any of the	system
       libraries or in multi-thread applications is unsupported.

       Very wide fields	(>128 characters) fail.

SunOS 5.9			  18 Feb 1993			  printf(3UCB)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | EXAMPLES | SEE ALSO | NOTES

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