clarified signature: more direct Isabelle_Process.EXIT;

proper arguments of protocol function;

merged

more robust: process stdout on Windows may contain CR;

clarified signature; more inlined protocol messages;

prefer system option: easier to make it default;

support multiple sessions, notably for "isabelle build -P -j2";

pretty formatting as in Isabelle/ML;

output prover messages;

clarified signature;

clarified signature: more robust;

proper parent base;

traditional print_mode for batch build;

proper support for "isabelle build -P Pure";

clarified signature: more robust bootstrap base;

proper startup for Pure: its use_prelude produces stdout before stderr protocol init;

proper context for loading Pure;

clarified signature of ML_Process vs. Isabelle_Process: proper support for "isabelle build -P -b";

close socket explicitly (idempotent);

more robust message_context and shutdown, e.g. after errors in protocol loop (see also 3f02bc5a5a03);

simplified code and proofs

automated proof

merged

cleaned proofs