Remove whitespace
Cosmetic changes
NULL file_actions are also empty
Add lfp_spawn_attributes_emptyp()
Cosmetic change
Use vfork() when safe
Add LFP_SPAWN_USEVFORK to allow forcing the use of vfork()
Fix vfork() auto-detection
Exit from lfp_execve() only in case of E2BIG or ENOMEM