Really perplexing problem with writing to files on server

[phpmaven]

I have following lines of code:
$handle = fopen("/usr/local/www/logs/test.log", "a");
fwrite($handle, "this is a test");
fclose($handle);

I have an Apache server with several virtual hosts running. One virtual host can run this code with no problem and the file gets created and written to. The same exact code fails on a different virtual host with "Warning: fopen(/usr/local/www/logs/test.log): failed to open stream: No such file or directory in..."

I'm totally baffled as to what the problem could be.

Thanks,

Mark

[lucy24]

From the Apache side:
Is each of the <VirtualHost> envelopes exactly, precisely identical, in every way, backward forward and sideways? Is the physical directory structure identical? (Not inside the various hosts, of course, just the directories you have to go through to get there.) Crystal ball says the solution will involve "But, but how could that possibly have had anything whatsoever to do with the problem?"

[whitespace]

From the PHP side:
Directory does not exist, directory permissions / ownership error? OPEN_BASEDIR restriction?

[phpmaven]

Thanks for the suggestions. Turns out that I'm an idiot. ;-)

[eeek]

Directory does not exist, directory permissions / ownership error? OPEN_BASEDIR restriction?

And is selinux involved?