988b1bb0c5
Implement persistent history storage: the strategy is simple at start: loads the existing .sh_history file at exit dump it. The implementation respects the HISTFILE variable and its POSIX definition: ~/.sh_history is used if HISTFILE is not set. to avoid sh to create the history file, set HISTSIZE to 0 or HISTFILE to en empty value Co-authored-by: pstef Reviewed by: jilles Differential Revision: https://reviews.freebsd.org/D29493