pls help me with this code
<?php $vote=$http_POST_VARS['vote'];if (!$db_conn = @mysql_connect('localhost','root','')){ echo'could not connect to db <br/>'; exit;}@mysql_select_db('poll');if (!empty($vote)){ $vote = addslashes($vote); $query = "update pool_results set num_votes = num_votes + 1 where candidate = '$vote'"; if(!($result =@mysql_query($query,$db_conn))){ echo' could not connect to db<br/>'; exit; }};$query = 'select* from poll_results';if(!($result =@mysql_query($query,$db_conn))){ echo' could not connect to db<br/>'; exit; }$num_candidates=mysql_num_rows($result);$total_votes=0;while ($row = mysql_fetch_object ($result)){$total_votes += $row->num_votes;}mysql_data_seek($result,0); putenv('GDFONTPATH=C:\WINNT\Fonts'); $width=500; $left_margin=50; $right_margin=50; $bar_height=40; $bar_spacing=$bar_height/2; $font='arial'; $title_size=16; $main_size=12; $small_size=12; $text_indent=10;$x=$left_margin+60;$y=50;$bar_unit=($width-($x+$right_margin))/100; $height = num_candidates*($bar_height+$bar_spacing)+50; $im = ImageCreate($width,$height); $white=ImageColorAllocate($im,255,255,255);$blue=ImageColorAllocate($im,0,64,128);$black=ImageColorAllocate($im,0,0,0);$pink=ImageColorAllocate($im,255,78,243); $text_color =$black; $percent_color=$black; $bg_color=$white; $line_color=$black; $bar_color=$blue; $number_color=$pink; ImageFilledRectangle($im,0,0,$width-1,$height-1,$bg_color); ImageRectangle($im,0,0,$width-1,$height-1,$line_color); $title='poll Results';$title_dimensions=ImageTTFBBox($title_size,0,$font,$title);$title_length = $title_dimensions[2]- $title_dimensions[0];$title_height=abs($title_dimensions[7]-$title_dimensions[1]);$title_above_line=abs($title_dimensions[7]);$title_x=($width-$title_length)/2;$title_y=($y-$title_height)/2 + $title_above_line;ImageTTFText($im,$title_size,0,$title_x,$title_y, $text_color,$font,$title); ImageLine($im,$x,$y-5,$x,$height-15,$line_color); while ($row = mysql_fetch_object($result)) { if($total_votes > 0) $percent = intval(round(($row->num_votes/$total_votes)*100)); else $percent = 0; ImageTTFText($im,$main_size,0,$width-30,$y+($bar_height/2), $percent_color,$font,$percent.'%'); if($total_votes > 0) $right_value = intval(round(($row->num_votes/$total_votes)*100)); else $right_value = 0; $bar_length = $x + ($right_value*$bar_unit);ImageFilledRectangle($im,$x,$y-2,$bar_length,$y+$bar_height,$bar_color); ImageTTFText($im,$main_size,0,$text_indent,$y+($bar_height/2), $text_color,$font,$row->candidate); ImageRectangle($im,$bar_lenght+1,$y-2, ($x+(100*$bar_unit)),$y+$bar_height,$line_color); ImageTTFText($im,$small_size,0,$x+(100*$bar_unit)-50,$y+($bar_height/2), $number_color,$font,$row->num_votes.'/'.$total_votes); $y=$y($bar_height+$bar_spacing); }header('content-type: image/png');ImagePng($im);ImageDestroy($im);?>
keep Poping with this error line? -->Fatal error: Call to undefined function: imagecreate() in c:\apache\htdocs\poll\tmp2igcqydwzo.php on line 61<-- and 1 more question, what is UNIX?how to config it?