Re: File locking issues

Hello Sascha, On 04-Jan-00 12:37:43, you wrote: >> Since we have to pass an opened file handle to flock(), if the file >> is closed with a pending lock, is that lock freed? > File descriptors are closed either explicitly by the program > or on process termination. > PHP's flock inherits the semantics of the underlying > implementation. Ok, thanks. What about in the Windows world? Does it work alike? Another question. What is the recomended sequence to assure that only a access will be able to write to a file at once? What I am doing is: 1) $file=fopen($filename,"w"); 2) flock($file,2); 3) fwrite($file,...) 4) flock($file,3); 5) fclose($file) Could two processes get to 2) and have one overwrite what the other just wrote to the file? To read I do: 1) $file=fopen($filename,"r") 2) flock($file,1); 3) fread($file); 4) flock($file,3); 5) fclose($file); I suppose this prevents a process to write to the file while it is written with the former access sequence while one or more processes are reading from the file with the later access sequence. I wonder if my concurrency analisys is correct. Regards, Manuel Lemos Web Programming Components using PHP Classes. Look at: http://phpclasses.UpperDesign.com/?user=mlemos@acm.org -- E-mail: mlemos@acm.org URL: http://www.mlemos.e-na.net/ PGP key: http://www.mlemos.e-na.net/ManuelLemos.pgp --