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PRINTF(3S)							    PRINTF(3S)

NAME
       printf, fprintf,	sprintf	- formatted output conversion

SYNOPSIS
       #include	<stdio.h>

       printf(format [,	arg ] ...  )
       char *format;

       fprintf(stream, format [, arg ] ...  )
       FILE *stream;
       char *format;

       sprintf(s, format [, arg	] ...  )
       char *s,	format;

DESCRIPTION
       Printf  places  output  on  the standard	output stream stdout.  Fprintf
       places output on	the named output stream.  Sprintf places  `output'  in
       the string s, followed by the character `\0'.

       Each of these functions converts, formats, and prints its arguments af-
       ter the first under control of the first	argument.  The first  argument
       is  a character string which contains two types of objects: plain char-
       acters, which are simply	copied to the output  stream,  and  conversion
       specifications,	each  of  which	 causes	conversion and printing	of the
       next successive arg printf.

       Each conversion specification is	introduced by the character  %.	  Fol-
       lowing the %, there may be

       -      an  optional  minus  sign	`-' which specifies left adjustment of
	      the converted value in the indicated field;

       -      an optional digit	string specifying a field width; if  the  con-
	      verted  value  has fewer characters than the field width it will
	      be blank-padded on the left (or right,  if  the  left-adjustment
	      indicator	 has  been  given)  to make up the field width;	if the
	      field width begins with a	zero, zero-padding will	 be  done  in-
	      stead of blank-padding;

       -      an optional period `.'  which serves to separate the field width
	      from the next digit string;

       -      an optional digit	string specifying a precision which  specifies
	      the  number  of digits to	appear after the decimal point,	for e-
	      and f-conversion,	or the maximum	number	of  characters	to  be
	      printed from a string;

       -      the character l specifying that a	following d, o,	x, or u	corre-
	      sponds to	a long integer arg.  (A	 capitalized  conversion  code
	      accomplishes the same thing.)

       -      a	 character  which  indicates  the type of conversion to	be ap-
	      plied.

       A field width or	precision may be `*' instead of	a  digit  string.   In
       this case an integer arg	supplies the field width or precision.

       The conversion characters and their meanings are

       dox    The  integer  arg	is converted to	decimal, octal,	or hexadecimal
	      notation respectively.

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

       e      The   float   or	 double	  arg	is   converted	in  the	 style
	      `[-]d.ddde+-dd' where there is  one  digit  before  the  decimal
	      point  and the number after is equal to the precision specifica-
	      tion for the argument; when the precision	is missing,  6	digits
	      are produced.

       g      The float	or double arg is printed in style d, in	style f, or in
	      style e, whichever gives full precision in minimum space.

       c      The character arg	is printed.  Null characters are ignored.

       s      Arg is taken to be a string (character pointer)  and  characters
	      from  the	string are printed until a null	character or until the
	      number of	characters indicated by	the precision specification is
	      reached; however if the precision	is 0 or	missing	all characters
	      up to a null are printed.

       u      The unsigned integer arg is converted  to	 decimal  and  printed
	      (the result will be in the range 0 to 65535).

       %      Print a `%'; no argument is converted.

       In no case does a non-existent or small field width cause truncation of
       a field;	padding	takes place only if the	specified field	width  exceeds
       the  actual  width.   Characters	 generated  by	printf	are printed by
       putc(3).

       Examples
       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 %d, %02d:%02d", weekday, month, day, hour,	min);

       To print	pi to 5	decimals:

	      printf("pi = %.5f", 4*atan(1.0));

SEE ALSO
       putc(3),	scanf(3), ecvt(3)

BUGS
       Very wide fields	(>128 characters) fail.

								    PRINTF(3S)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | BUGS

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