This flag is for ENGINEs who return new duplicate structures when found via
"ENGINE_by_id()". When an ENGINE must store state (eg. if ENGINE_ctrl()
commands are called in sequence as part of some stateful process like
key-generation setup and execution), it can set this flag - then each attempt
to obtain the ENGINE will result in it being copied into a new structure.
Normally, ENGINEs don't declare this flag so ENGINE_by_id() just increments
the existing ENGINE's structural reference count.
This flag is for ENGINEs who return new duplicate structures when found via "ENGINE_by_id()". When an ENGINE must store state (eg. if ENGINE_ctrl() commands are called in sequence as part of some stateful process like key-generation setup and execution), it can set this flag - then each attempt to obtain the ENGINE will result in it being copied into a new structure. Normally, ENGINEs don't declare this flag so ENGINE_by_id() just increments the existing ENGINE's structural reference count.