Resume Upload

resume.php

<?php 
$CHUNK = 8192; 

        try { 
            if (!($putData = fopen("php://input", "r"))) 
                throw new Exception("Can't get PUT data."); 

            // now the params can be used like any other variable 
            // see below after input has finished 

            $tot_write = 0; 
            $tmpFileName = "/var/dev/tmp/PUT_FILE"; 
            // Create a temp file 
            if (!is_file($tmpFileName)) { 
                fclose(fopen($tmpFileName, "x")); //create the file and close it 
                // Open the file for writing 
                if (!($fp = fopen($tmpFileName, "w"))) 
                    throw new Exception("Can't write to tmp file"); 

                // Read the data a chunk at a time and write to the file 
                while ($data = fread($putData, $CHUNK)) { 
                    $chunk_read = strlen($data); 
                    if (($block_write = fwrite($fp, $data)) != $chunk_read) 
                        throw new Exception("Can't write more to tmp file"); 

                    $tot_write += $block_write; 
                } 

                if (!fclose($fp)) 
                    throw new Exception("Can't close tmp file"); 

                unset($putData); 
            } else { 
                // Open the file for writing 
                if (!($fp = fopen($tmpFileName, "a"))) 
                    throw new Exception("Can't write to tmp file"); 

                // Read the data a chunk at a time and write to the file 
                while ($data = fread($putData, $CHUNK)) { 
                    $chunk_read = strlen($data); 
                    if (($block_write = fwrite($fp, $data)) != $chunk_read) 
                        throw new Exception("Can't write more to tmp file"); 

                    $tot_write += $block_write; 
                } 

                if (!fclose($fp)) 
                    throw new Exception("Can't close tmp file"); 

                unset($putData); 
            } 

            // Check file length and MD5 
            if ($tot_write != $file_size) 
                throw new Exception("Wrong file size"); 

            $md5_arr = explode(' ', exec("md5sum $tmpFileName")); 
            $md5 = $md5sum_arr[0]; 
            if ($md5 != $md5sum) 
                throw new Exception("Wrong md5"); 
        } catch (Exception $e) { 
            echo '', $e->getMessage(), "\n"; 
        }