Re: Blocking with fopen when file is already open for writing


Colin McKinnon wrote:
Efi Merdler wrote:

Hi,
I created a very simple application that reads and writes to a file, I
was wondering if fopen when opening a file for write access blocks
this file, i.e. when another user runs this script the script will
halt until the first user closes its file handle.


What happenned when you tested it?

Here's a hint:
<?php
print "ready to start\n";
flush();
$fh=fopen('/tmp/test','w');
if (is_resource($fh)) {
print "opened...\n";
flush();
sleep(30);
print "Exiting\n";
fclose($fh);
} else {
print "failed to open\n";
}
?>

(if you run two instances of this script, the second will do one of three
things - you've only considered two possibilities so far)

If not how can I change php behavior to block such access?


flock()

C.

Thanks,
I'll probably use a semaphore in order achieve this block behavior.

Efi

.

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