shell_init.c 28 interactive shell settings
               main.c 88 start of shell JOBC is ON
               main.c 64 [env -o] stack=[0] state=[4]
        token_print.c 29 13:[env]
        token_print.c 29 13:[-o]
               main.c 64 [env -u] stack=[0] state=[4]
        token_print.c 29 13:[env]
        token_print.c 29 13:[-u]
               main.c 64 [histor] stack=[0] state=[4]
        token_print.c 29 13:[histor]
               main.c 64 [history] stack=[0] state=[4]
        token_print.c 29 13:[history]
               main.c 64 [env -u LESS] stack=[0] state=[4]
        token_print.c 29 13:[env]
        token_print.c 29 13:[-u]
        token_print.c 29 13:[LESS]
               main.c 64 [env ] stack=[0] state=[0]
        token_print.c 29 13:[env]
         shell_exit.c 17 shell_exit()