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printf

printf [
filehandle
] 
format
, 
list

Prints a formatted string of the elements in list to filehandle or, if omitted, the currently selected output filehandle. This is similar to the C library's printf and fprintf functions, except that the * field width specifier is not supported. The function is exactly equivalent to:

print 
filehandle
 sprintf(
format
, 
list
);
printf and sprintf use the same format syntax, but sprintf only returns a string; it doesn't print to a filehandle. The format string contains text with embedded field specifiers into which the the elements of list are substituted in order, one per field. Field specifiers follow the form:
%
m.nx
A percent sign begins each field, and x is the type of field. The optional m gives the minimum field width for appropriate field types (negative m left-justifies). The .n gives the precision for a specific field type, such as the number of digits after a decimal point for floating-point numbers, the maximum length for a string, and the minimum length for an integer.

Field specifiers ( x ) may be the following:

Code Meaning
% Percent sign
c Character
d Decimal integer
e

Exponential format floating-point number

E

Exponential format floating-point number with uppercase E

f

Fixed-point format floating-point number

g

Floating-point number, in either exponential or fixed decimal notation

G

Like g with uppercase E (if applicable)

ld Long decimal integer
lo Long octal integer
lu Long unsigned decimal integer
lx Long hexadecimal integer
o Octal integer
s String
u Unsigned decimal integer
x Hexadecimal integer
X Hexadecimal integer with uppercase letters
p The Perl value's address in hexadecimal
n

Special value that stores the number of characters output so far into the next variable in the parameter list


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