* gnu-nat.c (gnu_attach): Add process to inferiors table.

	* gnu-nat.c (gnu_attach): Add process to inferiors table.
	(gnu_detach): Remove it.
	* go32-nat.c (go32_create_inferior): Add process to gdb's inferior
	table.
	* inf-ptrace.c (inf_ptrace_follow_fork): Delete and add inferiors
	to inferior table accordingly.
	(inf_ptrace_attach): Add new process to inferior table.
	(inf_ptrace_detach): Remove it.
	* inf-ttrace.c (inf_ttrace_follow_fork): Delete and add inferiors
	to inferior table accordingly.
	(inf_ttrace_attach): Add process to inferior table.
	(inf_ttrace_detach): Remove it.
	* linux-fork.c (init_fork_list): Delete any left over inferior.
	(linux_fork_mourn_inferior, detach_fork_command): Also delete
	processes from inferior list.
	* monitor.c (monitor_open): Add process to inferior list.
	(monitor_close): Remove it.
	* nto-procfs.c (procfs_attach): Add process to inferior list.
	Find threads after pushing the target.
	(procfs_detach): Remove process from inferior list.
	(procfs_create_inferior): Add process to inferior list.
	* procfs.c (procfs_detach): Remove process from inferior list.
	(do_attach): Add process to inferior list.
	* remote-sim.c (sim_create_inferior): Add process to inferior list.
	(gdbsim_close): Remove it.
	* target.c (generic_mourn_inferior): If inferior_ptid is not
	null_ptid, remove the corresponding inferior from inferior list.
	* win32-nat.c (do_initial_win32_stuff): Add process to inferior list.
	(win32_detach): Remove it.
	* linux-nat.c (linux_child_follow_fork): Delete and add inferiors
	to inferior list accordingly.
	* fork-child.c (fork_inferior): Add process to inferior list.
	* corelow.c (CORELOW_PID): Define.
	(core_close): Remove core from inferior list.
	(core_open): Add it.