#23258 [Asn]: fgets() hangs 15 seconds on EOF of a socket

ID: 23258 Updated by: wez@php.net Reported By: markus dot pfefferle at web dot de Status: Assigned Bug Type: Sockets related Operating System: Windows 2000 PHP Version: 4.3.2-RC Assigned To: wez New Comment: I must verify/fix this before 4.3.2 goes gold. Previous Comments: ------------------------------------------------------------------------ [2003-04-23 07:15:07] markus dot pfefferle at web dot de Back from Eastern holiday. Downloaded and installed the CVS snapshot (phpinfo() says build 2195) and tried it again. Same error - 15 seconds pause at the last (failing) read from a socket: 1051099825 : string(1) "" 1051099825 : string(1) "" 1051099825 : string(1) "" 1051099825 : string(1) "" 1051099841 : string(0) "" So ticket still open. ------------------------------------------------------------------------ [2003-04-17 09:40:23] wez@php.net Please try using this CVS snapshot: http://snaps.php.net/php4-STABLE-latest.tar.gz For Windows: http://snaps.php.net/win32/php4-win32-STABLE-latest.zip ------------------------------------------------------------------------ [2003-04-17 09:23:54] markus dot pfefferle at web dot de Err, nevermind. I figured out why - var_dump() writes to the output buffer before echo does. But in the end, the 15 second-problem remains. Here with fread($fp, 1): 1050589160 : string(1) "\n" 1050589160 : string(1) "\n" 1050589160 : string(1) "\n" 1050589160 : string(1) "\n" 1050589175 : string(0) "" It takes fread() and fgets() in Blocking mode 15 seconds to realize that the connection has been severed. ------------------------------------------------------------------------ [2003-04-17 09:13:58] markus dot pfefferle at web dot de The "Array" is a mistake actually - an output from another place of my code. Yet still the mystery remains, why the loop goes through another cycle after the last call to fgets() has returned false and feof() is not reflecting the end of the connection. And why $r in this case does not check out as "false" in an expression to preliminary end the loop. ------------------------------------------------------------------------ [2003-04-17 07:35:51] markus dot pfefferle at web dot de This well-known fragment of code takes up about 15 seconds on my machine: <pre> $fp = fsockopen($host, $port); fputs($fp, "POST $path HTTP/1.1\n"); fputs($fp, "Host: $host\n"); fputs($fp, "Content-type: application/x-www-form-urlencoded\n"); fputs($fp, "Content-length: ". strlen($data_to_send) ."\n"); fputs($fp, "Connection: close\n\n"); fputs($fp, "$data_to_send\n"); while(!feof($fp)) { $res .= fgets($fp, 128); } </pre> In order to trace the cause fot this pause, I modified whie while-loop to give me some debugging information: <pre> while(!feof($fp)) { $r = fgets($fp, 128); echo time()." : ".var_dump($r),"\n"; } </pre> Truns out this on the final 3 lines: <pre> 1050581993 : string(2) " " 1050581993 : bool(false) 1050582009 : Array </pre> The second line that returned false should already have flipped the EOF flag on the connection, but apparently it didn't. The last call that finally flips this flag however takes up 15 seconds of time and returns (odd enough) an empty array. Alrighty I think - if the false-value of the last chunk will give me a clue to break the loop, I just change my code to this: <pre> do { $r = fgets($fp, 128); echo time()." : ".var_dump($r),"\n"; } while ($r); </pre> And guess what - exactly the same 15 seconds, exactly the same output as before. The loop didn't even exit when $r was bool(false) according to var_dump(). This is what really puzzles me. I also used fread and toyed around with any possible length-parameter. It's always these 15 seconds delay at the last read that returns this odd empty array. ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=23258&edit=1