(command.CommandList
  children: [
    (command.ShAssignment
      pairs: [
        (assign_pair
          lhs: (sh_lhs_expr.Name name:tid)
          op: assign_op.Equal
          rhs: {(DQ <'broken pipe test'>)}
          spids: [7]
        )
      ]
    )
    (command.ForEach
      iter_name: p
      iter_words: [{(${ Id.VSub_Name SSH_PROTOCOLS)}]
      do_arg_iter: F
      body: 
        (command.DoGroup
          children: [
            (C {<trace>} {(DQ <'protocol '> ($ Id.VSub_DollarName '$p'))})
            (command.ForEach
              iter_name: i
              iter_words: [{<1>} {<2>} {<3>} {<4>}]
              do_arg_iter: F
              body: 
                (command.DoGroup
                  children: [
                    (command.Pipeline
                      children: [
                        (command.Simple
                          words: [
                            {(${ Id.VSub_Name SSH)}
                            {<-> ($ Id.VSub_DollarName '$p')}
                            {<-F>}
                            {($ Id.VSub_DollarName '$OBJ') <'/ssh_config_config'>}
                            {<nexthost>}
                            {<echo>}
                            {($ Id.VSub_DollarName '$i')}
                          ]
                          redirects: [
                            (redir
                              op: <Id.Redir_Great '2>'>
                              loc: (redir_loc.Fd fd:2)
                              arg: {<'/dev/null'>}
                            )
                          ]
                          do_fork: T
                        )
                        (C {<true>})
                      ]
                      negated: F
                    )
                    (command.ShAssignment
                      pairs: [
                        (assign_pair
                          lhs: (sh_lhs_expr.Name name:r)
                          op: assign_op.Equal
                          rhs: {($ Id.VSub_QMark '$?')}
                          spids: [80]
                        )
                      ]
                    )
                    (command.If
                      arms: [
                        (if_arm
                          cond: 
                            (condition.Shell
                              commands: [
                                (command.Sentence
                                  child: 
                                    (C {<Id.Lit_LBracket '['>} {($ Id.VSub_DollarName '$r')} {<-ne>} 
                                      {<0>} {<Id.Lit_RBracket ']'>}
                                    )
                                  terminator: <Id.Op_Semi _>
                                )
                              ]
                            )
                          action: [
                            (C {<fail>} 
                              {
                                (DQ <'broken pipe returns '> ($ Id.VSub_DollarName '$r') 
                                  <' for protocol '> ($ Id.VSub_DollarName '$p')
                                )
                              }
                            )
                          ]
                          spids: [84 97]
                        )
                      ]
                    )
                  ]
                )
            )
          ]
        )
    )
  ]
)