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PRINTF(1)		     General Commands Manual		       PRINTF(1)

NAME
     printf -- formatted output

SYNOPSIS
     printf format [arguments ...]

DESCRIPTION
     The printf utility formats and prints its arguments, after the first, under
     control  of  the  format.	 The format is a character string which contains
     three types of objects: plain characters, which are simply copied to  stan-
     dard  output,  character escape sequences which are converted and copied to
     the standard output, and format specifications, each of which causes print-
     ing of the next successive argument.

     The arguments after the first are treated as strings if  the  corresponding
     format is either c, b or s; otherwise it is evaluated as a C constant, with
     the following extensions:

	   *   A leading plus or minus sign is allowed.
	   *   If  the	leading character is a single or double quote, the value
	       is the ASCII code of the next character.

     The format string is reused as often as necessary to satisfy the arguments.
     Any extra format specifications are evaluated with zero or the null string.

     Character escape sequences are in backslash notation as defined in the ANSI
     X3.159-1989 ("ANSI C89"), with extensions.  The characters and their  mean-
     ings are as follows:

	   \a	   Write a <bell> character.
	   \b	   Write a <backspace> character.
	   \c	   Ignore remaining characters in this string.
	   \f	   Write a <form-feed> character.
	   \n	   Write a <new-line> character.
	   \r	   Write a <carriage return> character.
	   \t	   Write a <tab> character.
	   \v	   Write a <vertical tab> character.
	   \'	   Write a <single quote> character.
	   \\	   Write a backslash character.
	   \num
	   \0num   Write  an 8-bit character whose ASCII value is the 1-, 2-, or
		   3-digit octal number num.

     Each format specification is introduced by the percent  character	(``%'').
     The remainder of the format specification includes, in the following order:

     Zero or more of the following flags:

	     #	     A `#' character specifying that the value should be printed
		     in  an  ``alternate form''.  For c, d, and s, formats, this
		     option has no effect.  For the o formats the  precision  of
		     the number is increased to force the first character of the
		     output  string to a zero.	For the x (X) format, a non-zero
		     result has the string 0x (0X) prepended to it.  For  e,  E,
		     f, g, and G, formats, the result will always contain a dec-
		     imal point, even if no digits follow the point (normally, a
		     decimal  point only appears in the results of those formats
		     if a digit follows the decimal point).  For g  and  G  for-
		     mats,  trailing  zeros  are  not removed from the result as
		     they would otherwise be;

	     -	     A minus sign `-' which specifies  left  adjustment  of  the
		     output in the indicated field;

	     +	     A	`+'  character	specifying that there should always be a
		     sign placed before the number when using signed formats.

	     ` '     A space specifying that a blank should  be  left  before  a
		     positive  number  for  a  signed format.  A `+' overrides a
		     space if both are used;

	     0	     A zero `0' character indicating that zero-padding should be
		     used rather than blank-padding.  A `-' overrides a  `0'  if
		     both are used;

     Field Width:
	     An  optional  digit  string specifying a field width; if the output
	     string 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 (note that a leading zero is
	     a flag, but an embedded zero is part of a field width);

     Precision:
	     An optional period, `.', followed by an optional digit string  giv-
	     ing  a precision which specifies the number of digits to appear af-
	     ter the decimal point, for e and f formats, or the  maximum  number
	     of  characters  to be printed from a string; if the digit string is
	     missing, the precision is treated as zero;

     Format:
	     A character which indicates the type  of  format  to  use	(one  of
	     diouxXfwEgGcsb).

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

     The format characters and their meanings are:

     diouXx	 The argument is printed as a signed decimal (d or i),	unsigned
		 octal,  unsigned decimal, or unsigned hexadecimal (X or x), re-
		 spectively.

     f		 The argument is printed 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 precision is explicitly 0, no digits
		 and no decimal point are printed.

     eE 	 The argument is printed in the style  e  `[-d.ddd+/-dd]'  where
		 there	is one digit before the decimal point and the number af-
		 ter is equal to the precision specification for  the  argument;
		 when  the  precision is missing, 6 digits are produced.  An up-
		 per-case E is used for an `E' format.

     gG 	 The argument is printed in style f or in style e (E)  whichever
		 gives full precision in minimum space.

     c		 The first character of argument is printed.

     s		 Characters  from  the string argument are printed until the end
		 is reached or until the number of characters indicated  by  the
		 precision specification is reached; however if the precision is
		 0 or missing, all characters in the string are printed.

     b		 As for s, but interpret character escapes in backslash notation
		 in the string argument.

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

     The  decimal  point  character is defined in the program's locale (category
     LC_NUMERIC).

     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.

DIAGNOSTICS
     The printf utility exits 0 on success, and >0 if an error occurs.

COMPATIBILITY
     The traditional BSD behavior of converting arguments of numeric formats not
     beginning with a digit to the ASCII code of the first character is not sup-
     ported.

SEE ALSO
     echo(1), printf(3)

STANDARDS
     The printf command is expected to be compatible with the  IEEE  Std  1003.2
     ("POSIX.2") specification.

HISTORY
     The  printf command appeared in 4.3BSD-Reno.  It is modeled after the stan-
     dard library function, printf(3).

BUGS
     Since the floating point numbers are translated  from  ASCII  to  floating-
     point and then back again, floating-point precision may be lost.

     ANSI hexadecimal character constants were deliberately not provided.

     The  escape  sequence  \000  is the string terminator.  When present in the
     format, the format will be truncated at the \000 character.

FreeBSD 5.0			  June 6, 1993			       PRINTF(1)
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