FS_MBACKGROUND
if ((p->fs_flags & FS_MBACKGROUND)) {
if (newmf->mf_ops->fs_flags & FS_MBACKGROUND)
if (!fg && foreground && (m->mf_ops->fs_flags & FS_MBACKGROUND)) {
FS_MBACKGROUND
if (!error && !(mf->mf_ops->fs_flags & FS_MBACKGROUND)) {
#define FS_BACKGROUND (FS_MBACKGROUND|FS_UBACKGROUND)