Test it only after calling start_job_command for a new command line.
When no more cmds, just set C->file->update_status.
(start_job_command): When the last line is empty or under -n, set
C->file->update_status.
(start_waiting_job): Grok cs_not_started after start_job_command as success.
(new_job): Set C->file->update_status when there are no cmds.
(job_next_command): When out of lines, don't set CHILD->file->update_status or
CHILD->file->command_state.
Take new arg; if nonzero, also double $s.
(main): Define MAKEOVERRIDES from command_variables here.
(define_makeflags): Don't use command_variables here; instead write a
reference $(MAKEOVERRIDES) in MAKEFLAGS. Make vars recursive.
returns EOF. Initialize C to zero before loop; in loop if C is EOF, set
optarg from ARGV[optind++], else call getopt_long.
(decode_env_switches): Use variable_expand instead of
allocated_variable_expand. Allocate a fresh buffer to copy split words
into; scan characters by hand to break words and debackslashify.
(shell_quote): New function.
(define_makeflags): Allocate doubled space for switch args, and command
variable names and values; use shell_quote to quote those things.
(command_variables): New type and variable.
(decode_switches, decode_env_switches): After making a variable definition,
record the struct variable pointer in the command_variables chain.
(define_makeflags): If ALL, write variable definitions for
command_variables.
(goals, lastgoal): New static variables (moved from auto in main).
(main): Don't process OTHER_ARGS at all.
Don't set variable MAKEOVERRIDES at all; define MAKE to just $(MAKE_COMMAND).
(init_switches): Prepend a - (return in order) instead of a + (require order).
(decode_switches): Don't set OTHER_ARGS at all.
Grok '\0' return from getopt_long as non-option argument; try variable
definition and (if !ENV) enter goal targets here.
(decode_env_switches): Use allocated_variable_expand to store value.
Use find_next_token to simplify word-splitting loop.
Don't prepend a dash to uninterpreted value.
Instead, if split into only one word, try variable definition and failing
that prepend a dash to the word and pass it to decode_switches as a single arg.
cs_running on entry (meaning the commands actually just ran).
(update_file_1): Whenever we set FILE->update_status, call
notice_finished_file instead of just set_command_state.
