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        (word_part.ArithSub
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          action: [
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          action: [
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                (DQ <'Tracing exec()s'> ($ Id.VSub_DollarName '$ftext') <' for '> 
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                (bool_expr.Binary
                  op_id: Id.BoolBinary_GlobDEqual
                  left: {(command_sub left_token:<Id.Left_DollarParen '$('> child:(C {<uname>} {<-m>}))}
                  right: {<i> <Id.Lit_Other '*'>}
                )
            )
            (command.ShAssignment
              pairs: [
                (assign_pair
                  lhs: (sh_lhs_expr.Name name:bits)
                  op: assign_op.Equal
                  rhs: {<32>}
                  spids: [931]
                )
              ]
            )
          ]
        )
      ]
    )
    (command.DParen
      child: 
        (arith_expr.BinaryAssign
          op_id: Id.Arith_Equal
          left: <Id.Lit_ArithVarLike offset>
          right: 
            (arith_expr.Binary
              op_id: Id.Arith_Slash
              left: <Id.Lit_ArithVarLike bits>
              right: {<Id.Lit_Digits 8>}
            )
        )
    )
    (command.ShFunction
      name: makeprobe
      body: 
        (BraceGroup
          children: [
            (command.ShAssignment
              pairs: [
                (assign_pair
                  lhs: (sh_lhs_expr.Name name:func)
                  op: assign_op.Equal
                  rhs: {($ Id.VSub_Number '$1')}
                  spids: [958]
                )
              ]
            )
            (command.ShAssignment
              pairs: [
                (assign_pair
                  lhs: (sh_lhs_expr.Name name:kname)
                  op: assign_op.Equal
                  rhs: {<execsnoop_> ($ Id.VSub_DollarName '$func')}
                  spids: [962]
                )
              ]
            )
            (command.ShAssignment
              pairs: [
                (assign_pair
                  lhs: (sh_lhs_expr.Name name:kprobe)
                  op: assign_op.Equal
                  rhs: 
                    {(DQ <'p:'> ($ Id.VSub_DollarName '$kname') <' '> ($ Id.VSub_DollarName '$func'))}
                  spids: [967]
                )
              ]
            )
            (command.ShAssignment
              pairs: [
                (assign_pair
                  lhs: (sh_lhs_expr.Name name:i)
                  op: assign_op.Equal
                  rhs: {<0>}
                  spids: [976]
                )
              ]
            )
            (command.WhileUntil
              keyword: <Id.KW_While while>
              cond: 
                (condition.Shell
                  commands: [
                    (command.Sentence
                      child: 
                        (command.DParen
                          child: 
                            (arith_expr.Binary
                              op_id: Id.Arith_Less
                              left: <Id.Lit_ArithVarLike i>
                              right: 
                                (arith_expr.Binary
                                  op_id: Id.Arith_Plus
                                  left: <Id.Lit_ArithVarLike argc>
                                  right: {<Id.Lit_Digits 1>}
                                )
                            )
                        )
                      terminator: <Id.Op_Semi _>
                    )
                  ]
                )
              body: 
                (command.DoGroup
                  children: [
                    (command.ShAssignment
                      pairs: [
                        (assign_pair
                          lhs: (sh_lhs_expr.Name name:kprobe)
                          op: assign_op.Equal
                          rhs: 
                            {
                              (DQ ($ Id.VSub_DollarName '$kprobe') <' +0(+'> 
                                (word_part.ArithSub
                                  anode: 
                                    (arith_expr.Binary
                                      op_id: Id.Arith_Star
                                      left: <Id.Lit_ArithVarLike i>
                                      right: <Id.Lit_ArithVarLike offset>
                                    )
                                ) <'(%si)):string'>
                              )
                            }
                          spids: [1005]
                        )
                      ]
                    )
                    (command.DParen
                      child: 
                        (arith_expr.UnaryAssign
                          op_id: Id.Node_PostDPlus
                          child: <Id.Lit_ArithVarLike i>
                        )
                    )
                  ]
                )
            )
          ]
        )
    )
    (C {<makeprobe>} {<sys_execve>})
    (command.Simple
      words: [{<echo>} {<nop>}]
      redirects: [(redir op:<Id.Redir_Great '>'> loc:(redir_loc.Fd fd:1) arg:{<current_tracer>})]
      do_fork: T
    )
    (command.If
      arms: [
        (if_arm
          cond: 
            (condition.Shell
              commands: [
                (command.Sentence
                  child: 
                    (command.Pipeline
                      children: [
                        (command.Simple
                          words: [{<echo>} {($ Id.VSub_DollarName '$kprobe')}]
                          redirects: [
                            (redir
                              op: <Id.Redir_DGreat '>>'>
                              loc: (redir_loc.Fd fd:1)
                              arg: {<kprobe_events>}
                            )
                            (redir
                              op: <Id.Redir_Great '2>'>
                              loc: (redir_loc.Fd fd:2)
                              arg: {<'/dev/null'>}
                            )
                          ]
                          do_fork: T
                        )
                      ]
                      negated: T
                    )
                  terminator: <Id.Op_Semi _>
                )
              ]
            )
          action: [
            (C {<makeprobe>} {<stub_execve>})
            (command.If
              arms: [
                (if_arm
                  cond: 
                    (condition.Shell
                      commands: [
                        (command.Sentence
                          child: 
                            (command.Pipeline
                              children: [
                                (command.Simple
                                  words: [{<echo>} {($ Id.VSub_DollarName '$kprobe')}]
                                  redirects: [
                                    (redir
                                      op: <Id.Redir_DGreat '>>'>
                                      loc: (redir_loc.Fd fd:1)
                                      arg: {<kprobe_events>}
                                    )
                                    (redir
                                      op: <Id.Redir_Great '2>'>
                                      loc: (redir_loc.Fd fd:2)
                                      arg: {<'/dev/null'>}
                                    )
                                  ]
                                  do_fork: T
                                )
                              ]
                              negated: T
                            )
                          terminator: <Id.Op_Semi _>
                        )
                      ]
                    )
                  action: [
                    (C {<makeprobe>} {<do_execve>})
                    (command.If
                      arms: [
                        (if_arm
                          cond: 
                            (condition.Shell
                              commands: [
                                (command.Sentence
                                  child: 
                                    (command.Pipeline
                                      children: [
                                        (command.Simple
                                          words: [{<echo>} {($ Id.VSub_DollarName '$kprobe')}]
                                          redirects: [
                                            (redir
                                              op: <Id.Redir_DGreat '>>'>
                                              loc: (redir_loc.Fd fd:1)
                                              arg: {<kprobe_events>}
                                            )
                                            (redir
                                              op: <Id.Redir_Great '2>'>
                                              loc: (redir_loc.Fd fd:2)
                                              arg: {<'/dev/null'>}
                                            )
                                          ]
                                          do_fork: T
                                        )
                                      ]
                                      negated: T
                                    )
                                  terminator: <Id.Op_Semi _>
                                )
                              ]
                            )
                          action: [(C {<edie>} {(DQ <'ERROR: adding a kprobe for execve. Exiting.'>)})]
                          spids: [1103 1119]
                        )
                      ]
                    )
                  ]
                  spids: [1079 1095]
                )
              ]
            )
          ]
          spids: [1055 1071]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: 
            (condition.Shell
              commands: [
                (command.Sentence
                  child: 
                    (command.Pipeline
                      children: [
                        (command.Simple
                          words: [{<echo>} {<1>}]
                          redirects: [
                            (redir
                              op: <Id.Redir_Great '>'>
                              loc: (redir_loc.Fd fd:1)
                              arg: {<'events/kprobes/'> ($ Id.VSub_DollarName '$kname') <'/enable'>}
                            )
                          ]
                          do_fork: T
                        )
                      ]
                      negated: T
                    )
                  terminator: <Id.Op_Semi _>
                )
              ]
            )
          action: [(C {<edie>} {(DQ <'ERROR: enabling kprobe for execve. Exiting.'>)})]
          spids: [1136 1151]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: 
            (condition.Shell
              commands: [
                (command.Sentence
                  child: 
                    (command.Pipeline
                      children: [
                        (command.Simple
                          words: [{<echo>} {<1>}]
                          redirects: [
                            (redir
                              op: <Id.Redir_Great '>'>
                              loc: (redir_loc.Fd fd:1)
                              arg: {<'events/sched/sched_process_fork/enable'>}
                            )
                          ]
                          do_fork: T
                        )
                      ]
                      negated: T
                    )
                  terminator: <Id.Op_Semi _>
                )
              ]
            )
          action: [(C {<edie>} {(DQ <'ERROR: enabling sched:sched_process_fork tracepoint. Exiting.'>)})]
          spids: [1162 1175]
        )
      ]
    )
    (C {<echo>} {(DQ <'Instrumenting '> ($ Id.VSub_DollarName '$func'))})
    (command.AndOr
      ops: [Id.Op_DAmp]
      children: [
        (command.DParen child:<Id.Lit_ArithVarLike opt_time>)
        (C {<printf>} {(DQ <'%-16s '>)} {(DQ <TIMEs>)})
      ]
    )
    (C {<printf>} {(DQ <'%6s %6s %s'> <Id.Lit_BadBackslash '\\'> <n>)} {(DQ <PID>)} {(DQ <PPID>)} 
      {(DQ <ARGS>)}
    )
    (command.ShAssignment
      pairs: [
        (assign_pair
          lhs: (sh_lhs_expr.Name name:offset)
          op: assign_op.Equal
          rhs: 
            {
              (command_sub
                left_token: <Id.Left_DollarParen '$('>
                child: 
                  (C {($ Id.VSub_DollarName '$awk')} 
                    {
                      (SQ <'BEGIN { o = 0; }\n'> 
                        <'\t$1 == "#" && $2 ~ /TASK/ && NF == 6 { o = 1; }\n'> <'\t$2 ~ /TASK/ { print o; exit }'>
                      )
                    } {<trace>}
                  )
              )
            }
          spids: [1254]
        )
      ]
    )
    (C {<warn>} {(DQ <'echo > trace'>)})
    (command.Pipeline
      children: [
        (command.Subshell
          child: 
            (command.If
              arms: [
                (if_arm
                  cond: 
                    (condition.Shell
                      commands: [
                        (command.Sentence
                          child: (command.DParen child:<Id.Lit_ArithVarLike opt_duration>)
                          terminator: <Id.Op_Semi _>
                        )
                      ]
                    )
                  action: [
                    (C {<sleep>} {($ Id.VSub_DollarName '$duration')})
                    (C {<cat>} {<-v>} {<trace>})
                  ]
                  spids: [1279 1289]
                )
              ]
              else_action: [(C {<cat>} {<-v>} {<trace_pipe>})]
            )
        )
        (C {($ 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 '$opt_time')} {<-v>} {<Id.Lit_VarLike 'kname='> ($ Id.VSub_DollarName '$kname')} {<-v>} 
          {<Id.Lit_VarLike 'opt_reexec='> ($ Id.VSub_DollarName '$opt_reexec')} 
          {
            (SQ <'\n'> <'\t# common fields\n'> <'\t$1 != "#" {\n'> 
              <'\t\t# task name can contain dashes\n'> <'\t\tcomm = pid = $1\n'> <'\t\tsub(/-[0-9][0-9]*/, "", comm)\n'> <'\t\tsub(/.*-/, "", pid)\n'> 
              <'\t}\n'> <'\n'> <'\t$1 != "#" && $(4+o) ~ /sched_process_fork/ {\n'> <'\t\tcpid=$0\n'> 
              <'\t\tsub(/.* child_pid=/, "", cpid)\n'> <'\t\tsub(/ .*/, "", cpid)\n'> <'\t\tgetppid[cpid] = pid\n'> <'\t\tdelete seen[pid]\n'> <'\t}\n'> <'\n'> 
              <'\t$1 != "#" && $(4+o) ~ kname {\n'> <'\t\tif (seen[pid])\n'> <'\t\t\tnext\n'> <'\t\tif (opt_name && comm !~ name)\n'> <'\t\t\tnext\n'> <'\n'> 
              <'\t\t#\n'> <'\t\t# examples:\n'> <'\t\t# ... arg1="/bin/echo" arg2="1" arg3="2" arg4="3" ...\n'> 
              <'\t\t# ... arg1="sleep" arg2="2" arg3=(fault) arg4="" ...\n'> <'\t\t# ... arg1="" arg2=(fault) arg3="" arg4="" ...\n'> 
              <'\t\t# the last example is uncommon, and may be a race.\n'> <'\t\t#\n'> <'\t\tif ($0 ~ /arg1=""/) {\n'> <'\t\t\targs = comm " [?]"\n'> <'\t\t} else {\n'> 
              <'\t\t\targs=$0\n'> <'\t\t\tsub(/ arg[0-9]*=\\(fault\\).*/, "", args)\n'> <'\t\t\tsub(/.*arg1="/, "", args)\n'> 
              <'\t\t\tgsub(/" arg[0-9]*="/, " ", args)\n'> <'\t\t\tsub(/"$/, "", args)\n'> <'\t\t\tif ($0 !~ /\\(fault\\)/)\n'> <'\t\t\t\targs = args " [...]"\n'> 
              <'\t\t}\n'> <'\n'> <'\t\tif (opt_time) {\n'> <'\t\t\ttime = $(3+o); sub(":", "", time)\n'> 
              <'\t\t\tprintf "%-16s ", time\n'> <'\t\t}\n'> <'\t\tprintf "%6s %6d %s\\n", pid, getppid[pid], args\n'> <'\t\tif (!opt_duration)\n'> 
              <'\t\t\tfflush()\n'> <'\t\tif (!opt_reexec) {\n'> <'\t\t\tseen[pid] = 1\n'> <'\t\t\tdelete getppid[pid]\n'> <'\t\t}\n'> 
              <'\t}\n'> <'\n'> <'\t$0 ~ /LOST.*EVENT[S]/ { print "WARNING: " $0 > "/dev/stderr" }\n'>
            )
          }
        )
      ]
      negated: F
    )
    (C {<end>})
  ]
)