=over

=item sprintf FORMAT, LIST

Returns a string formatted by the usual C<printf> conventions of the
C library function C<sprintf>.  See L<sprintf(3)> or L<printf(3)>
on your system for an explanation of the general principles.

Perl does its own C<sprintf> formatting--it emulates the C
function C<sprintf>, but it doesn't use it (except for floating-point
numbers, and even then only the standard modifiers are allowed).  As a
result, any non-standard extensions in your local C<sprintf> are not
available from Perl.

Perl's C<sprintf> permits the following universally-known conversions:

   %%	a percent sign
   %c	a character with the given number
   %s	a string
   %d	a signed integer, in decimal
   %u	an unsigned integer, in decimal
   %o	an unsigned integer, in octal
   %x	an unsigned integer, in hexadecimal
   %e	a floating-point number, in scientific notation
   %f	a floating-point number, in fixed decimal notation
   %g	a floating-point number, in %e or %f notation

In addition, Perl permits the following widely-supported conversions:

   %X	like %x, but using upper-case letters
   %E	like %e, but using an upper-case "E"
   %G	like %g, but with an upper-case "E" (if applicable)
   %b	an unsigned integer, in binary
   %p	a pointer (outputs the Perl value's address in hexadecimal)
   %n	special: *stores* the number of characters output so far
        into the next variable in the parameter list 

Finally, for backward (and we do mean "backward") compatibility, Perl
permits these unnecessary but widely-supported conversions:

   %i	a synonym for %d
   %D	a synonym for %ld
   %U	a synonym for %lu
   %O	a synonym for %lo
   %F	a synonym for %f

Perl permits the following universally-known flags between the C<%>
and the conversion letter:

   space   prefix positive number with a space
   +       prefix positive number with a plus sign
   -       left-justify within the field
   0       use zeros, not spaces, to right-justify
   #       prefix non-zero octal with "0", non-zero hex with "0x"
   number  minimum field width
   .number "precision": digits after decimal point for
           floating-point, max length for string, minimum length
           for integer
   l       interpret integer as C type "long" or "unsigned long"
   h       interpret integer as C type "short" or "unsigned short"
           If no flags, interpret integer as C type "int" or "unsigned"

There are also two Perl-specific flags:

   V       interpret integer as Perl's standard integer type
   v       interpret string as a vector of integers, output as
           numbers separated either by dots, or by an arbitrary
	   string received from the argument list when the flag
	   is preceded by C<*>

Where a number would appear in the flags, an asterisk (C<*>) may be
used instead, in which case Perl uses the next item in the parameter
list as the given number (that is, as the field width or precision).
If a field width obtained through C<*> is negative, it has the same
effect as the C<-> flag: left-justification.

The C<v> flag is useful for displaying ordinal values of characters
in arbitrary strings:

    printf "version is v%vd\n", $^V;		# Perl's version
    printf "address is %*vX\n", ":", $addr;	# IPv6 address
    printf "bits are %*vb\n", " ", $bits;	# random bitstring

If C<use locale> is in effect, the character used for the decimal
point in formatted real numbers is affected by the LC_NUMERIC locale.
See L<perllocale>.

If Perl understands "quads" (64-bit integers) (this requires
either that the platform natively support quads or that Perl
be specifically compiled to support quads), the characters

	d u o x X b i D U O

print quads, and they may optionally be preceded by

	ll L q

For example

	%lld %16LX %qo

You can find out whether your Perl supports quads via L<Config>:

	use Config;
	($Config{use64bitint} eq 'define' || $Config{longsize} == 8) &&
		print "quads\n";

If Perl understands "long doubles" (this requires that the platform
support long doubles), the flags

	e f g E F G

may optionally be preceded by

	ll L

For example

	%llf %Lg

You can find out whether your Perl supports long doubles via L<Config>:

	use Config;
	$Config{d_longdbl} eq 'define' && print "long doubles\n";

=back