man(1) Manual page archive


NAME
     printf - formatted print

SYNOPSIS
     printf(format, arg1, ...);
     char *format;

DESCRIPTION
     Printf converts, formats, and prints its arguments after the
     first under control of the first argument.  The first argu-
     ment 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 conversion and printing of the next successive argu-
     ment to printf.

     Each conversion specification is introduced by the character
     %.  Following the %, there may be

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

         - an optional digit string specifying a field width; if
           the converted argument 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;

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

         - an optional digit string (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;

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

     The conversion characters and their meanings are

        d
        o
        x  The integer argument is converted to decimal, octal,
           or hexadecimal notation respectively.

        f  The argument 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 dig-
           its are given; if the precision is explicitly 0, no
           digits and no decimal point are printed.  The argument

 1

           should be float or double.

        e  The argument 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 specification for the argument; when the
           precision is missing, 6 digits are produced.  The
           argument should be a float or double quantity.

        c  The argument character is printed.

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

        l  The argument is taken to be an unsigned integer which
           is converted to decimal and printed (the result will
           be in the range 0 to 65535).

     If no recognizable character appears after the %, that char-
     acter is printed; thus % may be printed by use of the string
     %%.  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 calling putchar.

SEE ALSO
     putchar (III)

BUGS
     Very wide fields (>128 characters)      fail.

 2