From code coverity scan, syscall return value must be check.

To not alter current behaviour, we simply log the problem,
so, if it occurs, the message will give explanation.

This are only warning as they don't block the server,
but such fail can explain strange (not expected) behaviour later.
Merge branch 'PHP-5.3' into PHP-5.4

* PHP-5.3:
  From code coverity scan, syscall return value must be check.
Merge branch 'PHP-5.4' into PHP-5.5

* PHP-5.4:
  From code coverity scan, syscall return value must be check.
Merge branch 'PHP-5.5'

* PHP-5.5:
  From code coverity scan, syscall return value must be check.