( resource handle, string format [, mixed args])
Write a string produced according to the formatting string
format to the stream resource specified
The format string is composed of zero or more directives:
ordinary characters (excluding %) that are
copied directly to the result, and conversion
specifications, each of which results in fetching its
own parameter. This applies to fprintf(),
sprintf(), and printf().
Each conversion specification consists of a percent sign
(%), followed by one or more of these
elements, in order:
An optional padding specifier that says
what character will be used for padding the results to the
right string size. This may be a space character or a
0 (zero character). The default is to pad
with spaces. An alternate padding character can be specified
by prefixing it with a single quote (').
See the examples below.
An optional alignment specifier that says
if the result should be left-justified or right-justified.
The default is right-justified; a -
character here will make it left-justified.
An optional number, a width specifier
that says how many characters (minimum) this conversion should
An optional precision specifier that says
how many decimal digits should be displayed for floating-point
numbers. This option has no effect for other types than
float. (Another function useful for formatting numbers is
A type specifier that says what type the
argument data should be treated as. Possible types:
% - a literal percent character. No
argument is required.
b - the argument is treated as an
integer, and presented as a binary number.
c - the argument is treated as an
integer, and presented as the character with that ASCII
d - the argument is treated as an
integer, and presented as a (signed) decimal number.
u - the argument is treated as an
integer, and presented as an unsigned decimal number.
f - the argument is treated as a
float, and presented as a floating-point number.
o - the argument is treated as an
integer, and presented as an octal number.
s - the argument is treated as and
presented as a string.
x - the argument is treated as an integer
and presented as a hexadecimal number (with lowercase
X - the argument is treated as an integer
and presented as a hexadecimal number (with uppercase
See also: printf(),