fopen（）无法打开流：权限被拒绝

Question

I'm trying to write to file, but PHP tells me that it's forbidden.

I tried to change permissions, assigned files to group 'apache' (according to <?php echo whoami(); ?>), but it didn't work.

Here is result of my file:

phpversion: 5.4.16
uname: Linux

exists // echo file_exists($file) ? ' exists' : ' does not exist', "
";
is readable // echo is_readable($file) ? ' is readable' : ' is NOT readable', "
";
is NOT writable // echo is_writable($file) ? ' is writable' : ' is NOT writable', "
";

Warning:  fopen(system/cache/cache.currency.1417623063): failed to open stream: Permission denied in /var/www/html/test/test.php on line 23
last error: array(4) {
  ["type"]=>
  int(2)
  ["message"]=>
  string(87) "fopen(system/cache/cache.currency.1417623063): failed to open stream: Permission denied"
  ["file"]=>
  string(30) "/var/www/html/test/test.php"
  ["line"]=>
  int(23)
}

Can you help me, please?

Answer 1

It was SELinux. It blocked all file changes, so I was able to read, but not write.