# 2.11BSD#431 - /usr/man/cat3/vfprintf.0

    PRINTF(3S)	    UNIX Programmer's Manual	       PRINTF(3S)

    NAME
         printf, fprintf, sprintf, vfprintf, vsprintf - formatted
         output conversion

    SYNOPSIS
         #include <stdio.h>

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

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

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

         #include <varargs.h>
         char *vprintf(format, args)
         char *format;
         va_list args;

         char *vfprintf(stream, format, args)
         FILE *stream;
         char *format;
         va_list args;

         int vsprintf(s, format, args)
         char *s, *format;
         va_list args;

    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'.  Alternate forms, in which the arguments have already
         been captured using the variable-length argument facilities
         of varargs(3), are available under the names vprintf,
         vfprintf, and vsprintf.

         Each of these functions converts, formats, and prints its
         arguments after the first under control of the first argu-
         ment.  The first argument is a character string which con-
         tains two types of objects: plain characters, which are sim-
         ply copied to the output stream, and conversion specifica-
         tions, each of which causes conversion and printing of the
         next successive arg printf.

         Each conversion specification is introduced by the character
         %.  The remainder of the conversion specification includes
         in the following order

    Printed 11/26/99	 August 10, 1988			1

    PRINTF(3S)	    UNIX Programmer's Manual	       PRINTF(3S)

         o+	  a minus sign `-' which specifies left adjustment of the
    	  converted value in the indicated field;

         o+	  an optional digit string specifying a field width; if
    	  the converted 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 instead of blank-
    	  padding;

         o+	  an optional period, followed by an optional digit
    	  string giving 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;

         o+	  the character l specifying that a following d, o, x, or
    	  u corresponds to a long integer arg;

         o+	  a character which indicates the type of conversion to
    	  be applied.

         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 signed decimal,
    	  unsigned octal, or unsigned hexadecimal notation
    	  respectively.

         f	  The float or double arg is converted to decimal nota-
    	  tion 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 expli-
    	  citly 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 pre-
    	  cision specification for the argument; when the preci-
    	  sion 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.

    Printed 11/26/99	 August 10, 1988			2

    PRINTF(3S)	    UNIX Programmer's Manual	       PRINTF(3S)

         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 through MAX-
    	  UINT, where MAXUINT equals 4294967295 on a VAX-11 and
    	  65535 on a PDP-11).

         %	  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 as by putc(3S).

    RETURN VALUE
         The functions all return the number of characters printed,
         or -1 if an error occurred.

    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(3S), scanf(3S)

    BUGS
         Very wide fields (>300 characters) fail.

         Only sprintf and vsprintf return a count of characters
         transferred.

         The functions still supports %D, %O, %U and %X.  Do not use
         these formats, as they will be disappearing real soon now.

    Printed 11/26/99	 August 10, 1988			3

Generated: 2016-12-26 | Generated by man2html V0.25 page hit count: 255 |