name=Document1.doc type=Word author=aAuthor 
name=Document1.doc type=Excel author=bAuthor
name=Document1.doc type=Text author=cAuthor
name=Document1.doc type=Excel author=dAuthor
name=Document1.doc type=Word author=eAuthor

##</code><code>##

name=Document1.doc type=Excel author=bAuthor
name=Document1.doc type=Excel author=dAuthor
name=Document1.doc type=Text author=cAuthor
name=Document1.doc type=Word author=aAuthor 
name=Document1.doc type=Word author=eAuthor

##</code><code>##

#$field is the position of the element (sort key) in the #line
   open INPUT , $input || die $input.$! ;

    while (<INPUT>) {
        @fields = split(" ",$_) ;
        push @{$hash{$fields[$field]}}, $_ ;
        $hash_keys{$fields[$field]} = $fields[$field] unless exists $hash_keys{$fields[1]} ;
    }
    for $element (sort keys %hash_keys) {
        open OUTPUT, ">>$output" || $output.$! ;
        print OUTPUT @{$hash{$element}} ;
        close OUTPUT ;
    }
    close INPUT ;