What if lil.php cannot write files?
Check directory ownership and permissions without making the entire site world-writable.
First run
The directory containing the self-extracting package must be writable by the PHP process long enough to create the final core, extension, key and setup files.
Normal work
Commands can modify only paths writable by the same PHP account. Use stat, attr and doctor to understand actual permissions.
Avoid 0777
Prefer correct ownership and the narrowest practical permissions. Global 0777 is not a universal fix and can weaken isolation on shared hosting.
Examples
doctorstat .attr .