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      ]
    )
    (C {(printf)} {(DQ ('%-16.16s %-6s %-8s %-10s %4s') (Id.Lit_Other '\\') (n))} {(DQ (COMM))} 
      {(DQ (PID))} {(DQ (TPID))} {(DQ (SIGNAL))} {(DQ (RETURN))}
    )
    (command.ShAssignment
      pairs: [
        (assign_pair
          lhs: (sh_lhs_expr.Name name:offset)
          op: assign_op.Equal
          rhs: 
            {
              (command_sub
                left_token: (Token id:Id.Left_DollarParen val:'$(' span_id:914)
                command_list: 
                  (command.CommandList
                    children: [
                      (C {($ Id.VSub_DollarName '$awk')} 
                        {
                          (SQ (Token id:Id.Lit_Chars val:'BEGIN { o = 0; }\n' span_id:918) 
                            (Token
                              id: Id.Lit_Chars
                              val: '    $1 == "#" && $2 ~ /TASK/ && NF == 6 { o = 1; }\n'
                              span_id: 919
                            ) (Token id:Id.Lit_Chars val:'    $2 ~ /TASK/ { print o; exit }' span_id:920)
                          )
                        } {(trace)}
                      )
                    ]
                  )
              )
            }
          spids: [913]
        )
      ]
    )
    (C {(warn)} {(DQ ('echo > trace'))})
    (command.Pipeline
      children: [
        (command.Subshell
          command_list: 
            (command.CommandList
              children: [
                (command.If
                  arms: [
                    (if_arm
                      cond: [
                        (command.Sentence
                          child: 
                            (command.DParen
                              child: 
                                (arith_expr.VarRef
                                  token: (Token id:Id.Lit_ArithVarLike val:opt_duration span_id:942)
                                )
                            )
                          terminator: (Token id:Id.Op_Semi val:';' span_id:946)
                        )
                      ]
                      action: [(C {(sleep)} {($ Id.VSub_DollarName '$duration')}) (C {(cat)} {(trace)})]
                      spids: [938 948]
                    )
                  ]
                  else_action: [(C {(cat)} {(trace_pipe)})]
                )
              ]
            )
        )
        (C {($ Id.VSub_DollarName '$awk')} {(-v)} 
          {(Id.Lit_VarLike 'o=') ($ Id.VSub_DollarName '$offset')} {(-v)} {(Id.Lit_VarLike 'opt_name=') ($ Id.VSub_DollarName '$opt_name')} {(-v)} 
          {(Id.Lit_VarLike 'name=') ($ Id.VSub_DollarName '$name')} {(-v)} {(Id.Lit_VarLike 'opt_duration=') ($ Id.VSub_DollarName '$opt_duration')} {(-v)} 
          {(Id.Lit_VarLike 'opt_time=') ($ Id.VSub_DollarName '$opt_time')} {(-v)} {(Id.Lit_VarLike 'opt_pid=') ($ Id.VSub_DollarName '$pid')} {(-v)} 
          {(Id.Lit_VarLike 'opt_fancy=') ($ Id.VSub_DollarName '$opt_fancy')} 
          {
            (SQ (Token id:Id.Lit_Chars val:'\n' span_id:1023) 
              (Token id:Id.Lit_Chars val:'    # fancy signal names\n' span_id:1024) (Token id:Id.Lit_Chars val:'    BEGIN {\n' span_id:1025) 
              (Token
                id: Id.Lit_Chars
                val: '        signals[1] = "SIGHUP"\n'
                span_id: 1026
              ) (Token id:Id.Lit_Chars val:'        signals[2] = "SIGINT"\n' span_id:1027) 
              (Token
                id: Id.Lit_Chars
                val: '        signals[3] = "SIGQUIT"\n'
                span_id: 1028
              ) (Token id:Id.Lit_Chars val:'        signals[4] = "SIGILL"\n' span_id:1029) 
              (Token
                id: Id.Lit_Chars
                val: '        signals[6] = "SIGABRT"\n'
                span_id: 1030
              ) (Token id:Id.Lit_Chars val:'        signals[8] = "SIGFPE"\n' span_id:1031) 
              (Token
                id: Id.Lit_Chars
                val: '        signals[9] = "SIGKILL"\n'
                span_id: 1032
              ) (Token id:Id.Lit_Chars val:'        signals[11] = "SIGSEGV"\n' span_id:1033) 
              (Token
                id: Id.Lit_Chars
                val: '        signals[13] = "SIGPIPE"\n'
                span_id: 1034
              ) (Token id:Id.Lit_Chars val:'        signals[14] = "SIGALRM"\n' span_id:1035) 
              (Token
                id: Id.Lit_Chars
                val: '        signals[15] = "SIGTERM"\n'
                span_id: 1036
              ) (Token id:Id.Lit_Chars val:'        signals[10] = "SIGUSR1"\n' span_id:1037) 
              (Token
                id: Id.Lit_Chars
                val: '        signals[12] = "SIGUSR2"\n'
                span_id: 1038
              ) (Token id:Id.Lit_Chars val:'        signals[17] = "SIGCHLD"\n' span_id:1039) 
              (Token
                id: Id.Lit_Chars
                val: '        signals[18] = "SIGCONT"\n'
                span_id: 1040
              ) (Token id:Id.Lit_Chars val:'        signals[19] = "SIGSTOP"\n' span_id:1041) 
              (Token
                id: Id.Lit_Chars
                val: '        signals[20] = "SIGTSTP"\n'
                span_id: 1042
              ) (Token id:Id.Lit_Chars val:'        signals[21] = "SIGTTIN"\n' span_id:1043) 
              (Token
                id: Id.Lit_Chars
                val: '        signals[22] = "SIGTTOU"\n'
                span_id: 1044
              ) (Token id:Id.Lit_Chars val:'    }\n' span_id:1045) (Token id:Id.Lit_Chars val:'\n' span_id:1046) 
              (Token id:Id.Lit_Chars val:'    # common fields\n' span_id:1047) (Token id:Id.Lit_Chars val:'    $1 != "#" {\n' span_id:1048) 
              (Token
                id: Id.Lit_Chars
                val: '        # task name can contain dashes\n'
                span_id: 1049
              ) (Token id:Id.Lit_Chars val:'        comm = pid = $1\n' span_id:1050) 
              (Token
                id: Id.Lit_Chars
                val: '        sub(/-[0-9][0-9]*/, "", comm)\n'
                span_id: 1051
              ) (Token id:Id.Lit_Chars val:'        if (opt_name && match(comm, name) == 0)\n' span_id:1052) 
              (Token id:Id.Lit_Chars val:'            next\n' span_id:1053) (Token id:Id.Lit_Chars val:'        sub(/.*-/, "", pid)\n' span_id:1054) 
              (Token id:Id.Lit_Chars val:'    }\n' span_id:1055) (Token id:Id.Lit_Chars val:'\n' span_id:1056) 
              (Token id:Id.Lit_Chars val:'    # sys_kill() entry\n' span_id:1057) (Token id:Id.Lit_Chars val:'    $1 != "#" && $(4+o) ~ /sys_kill/ && $(5+o) !~ /->/ {\n' span_id:1058) 
              (Token id:Id.Lit_Chars val:'        #\n' span_id:1059) (Token id:Id.Lit_Chars val:'        # eg: ... sys_kill(pid:...\n' span_id:1060) 
              (Token id:Id.Lit_Chars val:'        #\n' span_id:1061) (Token id:Id.Lit_Chars val:'        kpid = $(5+o)\n' span_id:1062) 
              (Token id:Id.Lit_Chars val:'        signal = $(7+o)\n' span_id:1063) (Token id:Id.Lit_Chars val:'        sub(/,$/, "", kpid)\n' span_id:1064) 
              (Token
                id: Id.Lit_Chars
                val: '        sub(/\\)$/, "", signal)\n'
                span_id: 1065
              ) (Token id:Id.Lit_Chars val:'        kpid = int("0x"kpid)\n' span_id:1066) 
              (Token
                id: Id.Lit_Chars
                val: '        signal = int("0x"signal)\n'
                span_id: 1067
              ) (Token id:Id.Lit_Chars val:'        current[pid,"kpid"] = kpid\n' span_id:1068) 
              (Token
                id: Id.Lit_Chars
                val: '        current[pid,"signal"] = signal\n'
                span_id: 1069
              ) (Token id:Id.Lit_Chars val:'    }\n' span_id:1070) (Token id:Id.Lit_Chars val:'\n' span_id:1071) 
              (Token id:Id.Lit_Chars val:'    # sys_kill exit\n' span_id:1072) (Token id:Id.Lit_Chars val:'    $1 != "#" && $(5+o) ~ /->/ {\n' span_id:1073) 
              (Token id:Id.Lit_Chars val:'        rv = int($NF)\n' span_id:1074) (Token id:Id.Lit_Chars val:'        killed_pid = current[pid,"kpid"]\n' span_id:1075) 
              (Token
                id: Id.Lit_Chars
                val: '        signal = current[pid,"signal"]\n'
                span_id: 1076
              ) (Token id:Id.Lit_Chars val:'\n' span_id:1077) 
              (Token
                id: Id.Lit_Chars
                val: '        delete current[pid,"kpid"]\n'
                span_id: 1078
              ) (Token id:Id.Lit_Chars val:'        delete current[pid,"signal"]\n' span_id:1079) 
              (Token id:Id.Lit_Chars val:'\n' span_id:1080) (Token id:Id.Lit_Chars val:'        if(opt_pid && killed_pid != opt_pid) {\n' span_id:1081) 
              (Token id:Id.Lit_Chars val:'            next\n' span_id:1082) (Token id:Id.Lit_Chars val:'        }\n' span_id:1083) (Token id:Id.Lit_Chars val:'\n' span_id:1084) 
              (Token id:Id.Lit_Chars val:'        if (opt_time) {\n' span_id:1085) (Token id:Id.Lit_Chars val:'            time = $(3+o); sub(":", "", time)\n' span_id:1086) 
              (Token
                id: Id.Lit_Chars
                val: '            printf "%-16s ", time\n'
                span_id: 1087
              ) (Token id:Id.Lit_Chars val:'        }\n' span_id:1088) (Token id:Id.Lit_Chars val:'\n' span_id:1089) 
              (Token id:Id.Lit_Chars val:'        if (opt_fancy) {\n' span_id:1090) (Token id:Id.Lit_Chars val:'            if (signals[signal] != "") {\n' span_id:1091) 
              (Token
                id: Id.Lit_Chars
                val: '                signal = signals[signal]\n'
                span_id: 1092
              ) (Token id:Id.Lit_Chars val:'            }\n' span_id:1093) 
              (Token id:Id.Lit_Chars val:'        }\n' span_id:1094) (Token id:Id.Lit_Chars val:'\n' span_id:1095) 
              (Token
                id: Id.Lit_Chars
                val: 
'        printf "%-16.16s %-6s %-8s %-10s %-4s\\n", comm, pid, killed_pid, signal,\n'
                span_id: 1096
              ) (Token id:Id.Lit_Chars val:'            rv\n' span_id:1097) 
              (Token id:Id.Lit_Chars val:'    }\n' span_id:1098) (Token id:Id.Lit_Chars val:'\n' span_id:1099) 
              (Token
                id: Id.Lit_Chars
                val: '    $0 ~ /LOST.*EVENTS/ { print "WARNING: " $0 > "/dev/stderr" }\n'
                span_id: 1100
              )
            )
          }
        )
      ]
      negated: F
    )
    (C {(end)})
  ]
)