* symm-nat.c (child_wait, _initialize_symm_nat, kill_inferior): Supply alternate version if ATTACH_DETACH is not defined. * ptx4-nat.c, config/i386/{nm-ptx4.h, ptx4.mh, ptx.mt, ptx4.mt, tm-ptx.h, tm-ptx4.h, xm-ptx.h, xm-ptx4.h}: New files. * configure.in: Recognize i[34]86-sequent-sysv4* host.