72 static struct subshell {  struct
74     struct subshell *prev;  // previous subshell data  argument
75     struct subshell *pipe;  // subshell where output goes to pipe on fork  argument
76     Dt_t *var;              // variable table at time of subshell  argument
78     Dt_t *sfun;             // function scope for subshell  argument
79     Dt_t *salias;           // alias scope for subshell  argument
80     Pathcomp_t *pathlist;   // for PATH variable
81     struct Error_context_s *errcontext;
96     int sig;      // signal for $$
105 } *active_subshell_data = NULL;  argument
117         struct subshell *sp = active_subshell_data->pipe;  in sh_subtmpfile()  argument