PRINTF(III) 9/17/73 PRINTF(III)
printf - formatted print
printf(format, arg , ...);
Printf converts, formats, and prints its arguments after the
first under control of the first argument. The first
argument 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
argument 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
- 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
The conversion characters and their meanings are
d The argument is converted to decimal notation.
o The argument is converted to octal notation. ``0''
will always appear as the first digit.
f The argument is converted to decimal notation in the
-]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. The argument
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 or character-pair 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
characters 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
character 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
Very wide fields (>128 characters) fail.