POSIX scripts that prepended FORTSH_RC_FILE=/dev/null now use
env \$RC_DISABLE_ENV — set by the profile system to the appropriate
rc-disable mechanism for each shell.
Also clean FORTSH_PATH -> RESOLVED_SHELL in run_posix_tests.sh.
39 files updated. SHELL_BIN is now required (no default path).
Scripts that previously defaulted to ../bin/fortsh now error
with "SHELL_BIN must be set" if the variable is unset.
test_abbr, test_defun, test_config, test_memory, test_perf, test_help
These test builtins unique to fortsh (abbreviations, function syntax,
memory pool stats, performance counters).
Source: fortsh/tests/builtins/
test_complete_compgen.sh, test_coproc.sh, test_let.sh — bash extensions
not part of POSIX but supported by bash, zsh, ksh, fortsh.
Source: fortsh/tests/builtins/