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Perl in a Nutshell

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Function Reference
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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:

CodeMeaning
%Percent sign
cCharacter
dDecimal 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)

ldLong decimal integer
loLong octal integer
luLong unsigned decimal integer
lxLong hexadecimal integer
oOctal integer
sString
uUnsigned decimal integer
xHexadecimal integer
XHexadecimal integer with uppercase letters
pThe 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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