This code requires that you use the PDFlib library for it to function properly.
<?php
$pdf = pdf_new(); //initialize new object
pdf_begin_document($pdf); //create new blank PDF
pdf_set_info($pdf, "Author", "John Doe"); //Set info about your PDF
pdf_set_info($pdf, "Title", "HelloWorld");
pdf_begin_page($pdf, (72 * 8.5), (72 * 11)); //specify page width and height
$font = pdf_findfont($pdf, "Times-Roman", "host", 0) //load a font
pdf_setfont($pdf, $font, 48); //set the font
pdf_set_text_pos($pdf, 50, 700); //assign text position
pdf_show($pdf, "Hello_World!"); //print text to assigned position
pdf_end_page($pdf); //end the page
pdf_end_document($pdf); //close the object
$document = pdf_get_buffer($pdf); //retrieve contents from buffer
$length = strlen($document); $filename = "HelloWorld.pdf"; //Finds PDF length and assigns file name
header("Content-Type:application/pdf");
header("Content-Length:" . $length);
header("Content-Disposition:inline; filename=" . $filename);
echo($document); //Send document to browser
unset($document); pdf_delete($pdf); //Clear Memory
?>