My eyes always miss this in the documentation, but starting in Perl 8.8 or thereabouts you can make a string into a file handle and then select it as the default file handle for write:

#make string into file handle

my $sBuf='';
open(my $fhOut, '>', \$sBuf); #\$sBuf is a reference to $sBuf

# make it your output stream for format/write
select $fhOut;

my ($sName, $iAge);

format SomeFormat =
Test: @<<<<<<<<<<<< @>>>>>
$sName, int($iAge)
.

$sName = "MickeyMouse";
$iAge = 82;   #born Nov, 1928
$~ = 'SomeFormat';
write;

print "buffer is: <$sBuf>\n";
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If you have perl 5.8.8 installed the documentation only shows up in open and not in perlopentut. In the Perl 5.12.2 documentation, there is a FAQ question devoted to this.

Alternatively, you can also try to follow the advice here to roll your own swrite() function.

Update: added sample code using string buffer file handle with format and write

Update: added the 5's, as per DrHyde below.

You do of course mean perl *5*.8.8 and *5*.12.2.

There's also IO::Scalar and IO::String on the CPAN.

sprintf and printf are your huckleberries...

The first argument is the format specification, which is then followed by a list of variables that directly correspond to the "placeholders" specified in the format.

For example,

printf "%05d", 32;  # prints an integer 5 digits wide, with leading ze
+roes, ie. 00032
printf "%32s", 'foo'; # prints the word 'foo' into an area 32 characte
+rs wide
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This doesn't even begin to scratch the surface of what sprint and printf do, but it is a place to start.

Show us the code you have tried.

format SIMPLE_TOP=
______________________________________________________________________
+_
@|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
"TITLE"
______________________________________________________________________
+_
@|||||||||||||||||... |@||||||||... @||||||||... |@||||||||||||||||||.
+..
"Variable1","Variable2","Variable3","Variable3"
______________________________________________________________________
+_
.

format SIMPLE=
@<<<<<<<<<<<<<<<<<... |@||||||||... @||||||||... |@||||||||||||||||||.
+..
    $varible,   $varible, $varible,  $varible
______________________________________________________________________
+_
.
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use Carp;
    sub swrite {
    croak "usage: swrite PICTURE ARGS" unless @_;
    my $format = shift;
    $^A = "";
    formline($format,@_);
    return $^A;
    }
    $string = swrite(<<'END', 1, 2, 3);
 Check me out
 @<<<  @|||  @>>>
 END
    print $string;
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Eep! Formats! I haven't seen those in YEARS! In fact I've not seen them used for nearly two *decades*! You should consider them to be obsolete, and find another way of formatting your output. sprintf() is probably the weapon of choice.

I just looking for way, to format somehow my output for easily reading. And I find those formats, I will try sprintf(),