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                    ('                 -D              # do not show function duration\n')
                    ('                 -h              # this usage message\n')
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                    ('       funcgraph -a do_sys_open    # include timestamps and process name\n')
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              right: (arith_expr.ArithWord w:{(Id.Lit_Digits 0)})
            )
        )
        (C {(usage)})
      ]
    )
    (command.AndOr
      ops: [Id.Op_DAmp]
      children: [
        (command.DParen
          child: 
            (arith_expr.Binary
              op_id: Id.Arith_DAmp
              left: (arith_expr.VarRef token:(Token id:Id.Lit_ArithVarLike val:opt_pid span_id:825))
              right: (arith_expr.VarRef token:(Token id:Id.Lit_ArithVarLike val:opt_tid span_id:829))
            )
        )
        (C {(edie)} {(DQ ('ERROR: You can use -p or -L but not both.'))})
      ]
    )
    (command.ShAssignment
      pairs: [
        (assign_pair
          lhs: (sh_lhs_expr.Name name:funcs)
          op: assign_op.Equal
          rhs: {(DQ ($ Id.VSub_Number '$1'))}
          spids: [842]
        )
      ]
    )
    (command.AndOr
      ops: [Id.Op_DAmp]
      children: [
        (command.DParen
          child: (arith_expr.VarRef token:(Token id:Id.Lit_ArithVarLike val:opt_pid span_id:849))
        )
        (command.ShAssignment
          pairs: [
            (assign_pair
              lhs: (sh_lhs_expr.Name name:pidtext)
              op: assign_op.Equal
              rhs: {(DQ (' for PID ') ($ Id.VSub_DollarName '$pid'))}
              spids: [856]
            )
          ]
        )
      ]
    )
    (command.AndOr
      ops: [Id.Op_DAmp]
      children: [
        (command.DParen
          child: (arith_expr.VarRef token:(Token id:Id.Lit_ArithVarLike val:opt_tid span_id:864))
        )
        (command.ShAssignment
          pairs: [
            (assign_pair
              lhs: (sh_lhs_expr.Name name:pidtext)
              op: assign_op.Equal
              rhs: {(DQ (' for TID ') ($ Id.VSub_DollarName '$tid'))}
              spids: [871]
            )
          ]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.DParen
                  child: 
                    (arith_expr.VarRef
                      token: (Token id:Id.Lit_ArithVarLike val:opt_duration span_id:881)
                    )
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:885)
            )
          ]
          action: [
            (C {(echo)} 
              {
                (DQ ('Tracing ') 
                  (word_part.EscapedLiteral
                    token: (Token id:Id.Lit_EscapedChar val:'\\"' span_id:894)
                  ) ($ Id.VSub_DollarName '$funcs') 
                  (word_part.EscapedLiteral
                    token: (Token id:Id.Lit_EscapedChar val:'\\"' span_id:896)
                  ) ($ Id.VSub_DollarName '$pidtext') (' for ') ($ Id.VSub_DollarName '$duration') (' seconds...')
                )
              }
            )
          ]
          spids: [877 887]
        )
      ]
      else_action: [
        (C {(echo)} 
          {
            (DQ ('Tracing ') 
              (word_part.EscapedLiteral
                token: (Token id:Id.Lit_EscapedChar val:'\\"' span_id:910)
              ) ($ Id.VSub_DollarName '$funcs') 
              (word_part.EscapedLiteral
                token: (Token id:Id.Lit_EscapedChar val:'\\"' span_id:912)
              ) ($ Id.VSub_DollarName '$pidtext') ('... Ctrl-C to end.')
            )
          }
        )
      ]
    )
    (command.AndOr
      ops: [Id.Op_DPipe]
      children: [
        (C {(cd)} {($ Id.VSub_DollarName '$tracing')})
        (C {(die)} 
          {
            (DQ ('ERROR: accessing tracing. Root user? Kernel has FTRACE?\n') 
              ('    debugfs mounted? (mount -t debugfs debugfs /sys/kernel/debug)')
            )
          }
        )
      ]
    )
    (command.AndOr
      ops: [Id.Op_DAmp]
      children: [
        (command.DBracket
          expr: (bool_expr.Unary op_id:Id.BoolUnary_e child:{($ Id.VSub_DollarName '$flock')})
        )
        (C {(die)} 
          {
            (DQ ('ERROR: ftrace may be in use by PID ') 
              (command_sub
                left_token: (Token id:Id.Left_DollarParen val:'$(' span_id:954)
                command_list: 
                  (command.CommandList
                    children: [(C {(cat)} {($ Id.VSub_DollarName '$flock')})]
                  )
              ) (' ') ($ Id.VSub_DollarName '$flock')
            )
          }
        )
      ]
    )
    (command.AndOr
      ops: [Id.Op_DPipe]
      children: [
        (command.Simple
          words: [{(echo)} {($ Id.VSub_Dollar '$$')}]
          redirects: [
            (redir.Redir
              op: (Token id:Id.Redir_Great val:'>' span_id:967)
              fd: -1
              arg_word: {($ Id.VSub_DollarName '$flock')}
            )
          ]
        )
        (C {(die)} {(DQ ('ERROR: unable to write ') ($ Id.VSub_DollarName '$flock') (.))})
      ]
    )
    (command.ShAssignment
      pairs: [
        (assign_pair
          lhs: (sh_lhs_expr.Name name:wroteflock)
          op: assign_op.Equal
          rhs: {(1)}
          spids: [981]
        )
      ]
    )
    (C {(sysctl)} {(-q)} {(kernel.ftrace_enabled) (Id.Lit_Equals '=') (1)})
    (command.Simple
      words: [{(read)} {(mode)}]
      redirects: [
        (redir.Redir
          op: (Token id:Id.Redir_Less val:'<' span_id:1003)
          fd: -1
          arg_word: {(current_tracer)}
        )
      ]
    )
    (command.AndOr
      ops: [Id.Op_DAmp]
      children: [
        (command.DBracket
          expr: 
            (bool_expr.Binary
              op_id: Id.BoolBinary_GlobNEqual
              left: {(DQ ($ Id.VSub_DollarName '$mode'))}
              right: {(DQ (nop))}
            )
        )
        (C {(edie)} 
          {(DQ ('ERROR: ftrace active (current_tracer=') ($ Id.VSub_DollarName '$mode') (')'))}
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.DParen
                  child: 
                    (arith_expr.VarRef
                      token: (Token id:Id.Lit_ArithVarLike val:opt_max span_id:1035)
                    )
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1039)
            )
          ]
          action: [
            (command.If
              arms: [
                (if_arm
                  cond: [
                    (command.Sentence
                      child: 
                        (command.Pipeline
                          children: [
                            (command.Simple
                              words: [{(echo)} {($ Id.VSub_DollarName '$max')}]
                              redirects: [
                                (redir.Redir
                                  op: (Token id:Id.Redir_Great val:'>' span_id:1052)
                                  fd: -1
                                  arg_word: {(max_graph_depth)}
                                )
                              ]
                            )
                          ]
                          negated: T
                        )
                      terminator: (Token id:Id.Op_Semi val:';' span_id:1055)
                    )
                  ]
                  action: [
                    (C {(edie)} 
                      {
                        (DQ ('ERROR: setting -m ') ($ Id.VSub_DollarName '$max') 
                          ('. Older kernel version? Exiting.')
                        )
                      }
                    )
                  ]
                  spids: [1044 1057]
                )
              ]
            )
          ]
          spids: [1031 1041]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.DParen
                  child: 
                    (arith_expr.VarRef
                      token: (Token id:Id.Lit_ArithVarLike val:opt_pid span_id:1077)
                    )
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1081)
            )
          ]
          action: [
            (command.Simple
              words: [{(echo)}]
              redirects: [
                (redir.Redir
                  op: (Token id:Id.Redir_Great val:'>' span_id:1088)
                  fd: -1
                  arg_word: {(set_ftrace_pid)}
                )
              ]
            )
            (command.ForEach
              iter_name: tid
              iter_words: [{(/proc/) ($ Id.VSub_DollarName '$pid') (/task/) (Id.Lit_Star '*')}]
              do_arg_iter: F
              body: 
                (command.DoGroup
                  children: [
                    (command.If
                      arms: [
                        (if_arm
                          cond: [
                            (command.Sentence
                              child: 
                                (command.Pipeline
                                  children: [
                                    (command.Simple
                                      words: [
                                        {(echo)}
                                        {
                                          (braced_var_sub
                                            token: (Token id:Id.VSub_Name val:tid span_id:1119)
                                            suffix_op: 
                                              (suffix_op.Unary
                                                op_id: Id.VOp1_DPound
                                                arg_word: {('*') (Id.Lit_Slash /)}
                                              )
                                          )
                                        }
                                      ]
                                      redirects: [
                                        (redir.Redir
                                          op: (Token id:Id.Redir_DGreat val:'>>' span_id:1125)
                                          fd: -1
                                          arg_word: {(set_ftrace_pid)}
                                        )
                                      ]
                                    )
                                  ]
                                  negated: T
                                )
                              terminator: (Token id:Id.Op_Semi val:';' span_id:1128)
                            )
                          ]
                          action: [
                            (C {(edie)} 
                              {
                                (DQ ('ERROR: setting -p ') ($ Id.VSub_DollarName '$pid') 
                                  (' (PID exist?). Exiting.')
                                )
                              }
                            )
                          ]
                          spids: [1112 1130]
                        )
                      ]
                    )
                  ]
                )
            )
          ]
          spids: [1073 1083]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.DParen
                  child: 
                    (arith_expr.VarRef
                      token: (Token id:Id.Lit_ArithVarLike val:opt_tid span_id:1153)
                    )
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1157)
            )
          ]
          action: [
            (command.If
              arms: [
                (if_arm
                  cond: [
                    (command.Sentence
                      child: 
                        (command.Pipeline
                          children: [
                            (command.Simple
                              words: [{(echo)} {($ Id.VSub_DollarName '$tid')}]
                              redirects: [
                                (redir.Redir
                                  op: (Token id:Id.Redir_Great val:'>' span_id:1170)
                                  fd: -1
                                  arg_word: {(set_ftrace_pid)}
                                )
                              ]
                            )
                          ]
                          negated: T
                        )
                      terminator: (Token id:Id.Op_Semi val:';' span_id:1173)
                    )
                  ]
                  action: [
                    (C {(edie)} 
                      {
                        (DQ ('ERROR: setting -L ') ($ Id.VSub_DollarName '$tid') 
                          (' (TID exist?). Exiting.')
                        )
                      }
                    )
                  ]
                  spids: [1162 1175]
                )
              ]
            )
          ]
          spids: [1149 1159]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.Pipeline
                  children: [
                    (command.Simple
                      words: [{(echo)}]
                      redirects: [
                        (redir.Redir
                          op: (Token id:Id.Redir_Great val:'>' span_id:1197)
                          fd: -1
                          arg_word: {(set_ftrace_filter)}
                        )
                      ]
                    )
                  ]
                  negated: T
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1200)
            )
          ]
          action: [(C {(edie)} {(DQ ('ERROR: writing to set_ftrace_filter. Exiting.'))})]
          spids: [1191 1202]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.Pipeline
                  children: [
                    (command.Simple
                      words: [{(echo)} {(DQ ($ Id.VSub_DollarName '$funcs'))}]
                      redirects: [
                        (redir.Redir
                          op: (Token id:Id.Redir_Great val:'>' span_id:1223)
                          fd: -1
                          arg_word: {(set_graph_function)}
                        )
                      ]
                    )
                  ]
                  negated: T
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1226)
            )
          ]
          action: [
            (C {(edie)} 
              {
                (DQ ('ERROR: enabling ') 
                  (word_part.EscapedLiteral
                    token: (Token id:Id.Lit_EscapedChar val:'\\"' span_id:1235)
                  ) ($ Id.VSub_DollarName '$funcs') 
                  (word_part.EscapedLiteral
                    token: (Token id:Id.Lit_EscapedChar val:'\\"' span_id:1237)
                  ) ('. Exiting.')
                )
              }
            )
          ]
          spids: [1213 1228]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.Pipeline
                  children: [
                    (command.Simple
                      words: [{(echo)} {(function_graph)}]
                      redirects: [
                        (redir.Redir
                          op: (Token id:Id.Redir_Great val:'>' span_id:1251)
                          fd: -1
                          arg_word: {(current_tracer)}
                        )
                      ]
                    )
                  ]
                  negated: T
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1254)
            )
          ]
          action: [
            (C {(edie)} 
              {
                (DQ ('ERROR: setting current_tracer to ') 
                  (word_part.EscapedLiteral
                    token: (Token id:Id.Lit_EscapedChar val:'\\"' span_id:1263)
                  ) (function) (word_part.EscapedLiteral token:(Token id:Id.Lit_EscapedChar val:'\\"' span_id:1265)) 
                  ('. Exiting.')
                )
              }
            )
          ]
          spids: [1243 1256]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.DParen
                  child: 
                    (arith_expr.VarRef
                      token: (Token id:Id.Lit_ArithVarLike val:opt_cpu span_id:1275)
                    )
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1279)
            )
          ]
          action: [
            (command.If
              arms: [
                (if_arm
                  cond: [
                    (command.Sentence
                      child: 
                        (command.Pipeline
                          children: [
                            (command.Simple
                              words: [{(echo)} {(nosleep-time)}]
                              redirects: [
                                (redir.Redir
                                  op: (Token id:Id.Redir_Great val:'>' span_id:1292)
                                  fd: -1
                                  arg_word: {(trace_options)}
                                )
                              ]
                            )
                          ]
                          negated: T
                        )
                      terminator: (Token id:Id.Op_Semi val:';' span_id:1295)
                    )
                  ]
                  action: [(C {(edie)} {(DQ ('ERROR: setting -C (nosleep-time). Exiting.'))})]
                  spids: [1284 1297]
                )
              ]
            )
          ]
          spids: [1271 1281]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.DParen
                  child: 
                    (arith_expr.VarRef
                      token: (Token id:Id.Lit_ArithVarLike val:opt_time span_id:1318)
                    )
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1322)
            )
          ]
          action: [
            (command.If
              arms: [
                (if_arm
                  cond: [
                    (command.Sentence
                      child: 
                        (command.Pipeline
                          children: [
                            (command.Simple
                              words: [{(echo)} {(funcgraph-abstime)}]
                              redirects: [
                                (redir.Redir
                                  op: (Token id:Id.Redir_Great val:'>' span_id:1335)
                                  fd: -1
                                  arg_word: {(trace_options)}
                                )
                              ]
                            )
                          ]
                          negated: T
                        )
                      terminator: (Token id:Id.Op_Semi val:';' span_id:1338)
                    )
                  ]
                  action: [(C {(edie)} {(DQ ('ERROR: setting -t (funcgraph-abstime). Exiting.'))})]
                  spids: [1327 1340]
                )
              ]
            )
          ]
          spids: [1314 1324]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.DParen
                  child: 
                    (arith_expr.VarRef
                      token: (Token id:Id.Lit_ArithVarLike val:opt_proc span_id:1358)
                    )
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1362)
            )
          ]
          action: [
            (command.If
              arms: [
                (if_arm
                  cond: [
                    (command.Sentence
                      child: 
                        (command.Pipeline
                          children: [
                            (command.Simple
                              words: [{(echo)} {(funcgraph-proc)}]
                              redirects: [
                                (redir.Redir
                                  op: (Token id:Id.Redir_Great val:'>' span_id:1375)
                                  fd: -1
                                  arg_word: {(trace_options)}
                                )
                              ]
                            )
                          ]
                          negated: T
                        )
                      terminator: (Token id:Id.Op_Semi val:';' span_id:1378)
                    )
                  ]
                  action: [(C {(edie)} {(DQ ('ERROR: setting -P (funcgraph-proc). Exiting.'))})]
                  spids: [1367 1380]
                )
              ]
            )
          ]
          spids: [1354 1364]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.DParen
                  child: 
                    (arith_expr.VarRef
                      token: (Token id:Id.Lit_ArithVarLike val:opt_tail span_id:1398)
                    )
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1402)
            )
          ]
          action: [
            (command.If
              arms: [
                (if_arm
                  cond: [
                    (command.Sentence
                      child: 
                        (command.Pipeline
                          children: [
                            (command.Simple
                              words: [{(echo)} {(funcgraph-tail)}]
                              redirects: [
                                (redir.Redir
                                  op: (Token id:Id.Redir_Great val:'>' span_id:1415)
                                  fd: -1
                                  arg_word: {(trace_options)}
                                )
                              ]
                            )
                          ]
                          negated: T
                        )
                      terminator: (Token id:Id.Op_Semi val:';' span_id:1418)
                    )
                  ]
                  action: [
                    (C {(edie)} {(DQ ('ERROR: setting -T (funcgraph-tail). Old kernel? Exiting.'))})
                  ]
                  spids: [1407 1420]
                )
              ]
            )
          ]
          spids: [1394 1404]
        )
      ]
    )
    (command.If
      arms: [
        (if_arm
          cond: [
            (command.Sentence
              child: 
                (command.DParen
                  child: 
                    (arith_expr.VarRef
                      token: (Token id:Id.Lit_ArithVarLike val:opt_nodur span_id:1438)
                    )
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1442)
            )
          ]
          action: [
            (command.If
              arms: [
                (if_arm
                  cond: [
                    (command.Sentence
                      child: 
                        (command.Pipeline
                          children: [
                            (command.Simple
                              words: [{(echo)} {(nofuncgraph-duration)}]
                              redirects: [
                                (redir.Redir
                                  op: (Token id:Id.Redir_Great val:'>' span_id:1455)
                                  fd: -1
                                  arg_word: {(trace_options)}
                                )
                              ]
                            )
                          ]
                          negated: T
                        )
                      terminator: (Token id:Id.Op_Semi val:';' span_id:1458)
                    )
                  ]
                  action: [(C {(edie)} {(DQ ('ERROR: setting -D (nofuncgraph-duration). Exiting.'))})]
                  spids: [1447 1460]
                )
              ]
            )
          ]
          spids: [1434 1444]
        )
      ]
    )
    (C {(warn)} {(DQ ('echo > trace'))})
    (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:1488)
                    )
                )
              terminator: (Token id:Id.Op_Semi val:';' span_id:1492)
            )
          ]
          action: [
            (C {(sleep)} {($ Id.VSub_DollarName '$duration')})
            (command.If
              arms: [
                (if_arm
                  cond: [
                    (command.Sentence
                      child: 
                        (command.DParen
                          child: 
                            (arith_expr.VarRef
                              token: (Token id:Id.Lit_ArithVarLike val:opt_headers span_id:1506)
                            )
                        )
                      terminator: (Token id:Id.Op_Semi val:';' span_id:1510)
                    )
                  ]
                  action: [(C {(cat)} {(trace)})]
                  spids: [1502 1512]
                )
              ]
              else_action: [
                (C {(grep)} {(-v)} {(SQ (Token id:Id.Lit_Chars val:'^#' span_id:1528))} {(trace)})
              ]
            )
          ]
          spids: [1484 1494]
        )
      ]
      else_action: [
        (command.AndOr
          ops: [Id.Op_DAmp]
          children: [
            (command.DParen
              child: 
                (arith_expr.VarRef
                  token: (Token id:Id.Lit_ArithVarLike val:opt_headers span_id:1545)
                )
            )
            (C {(cat)} {(trace)})
          ]
        )
        (C {(cat)} {(trace_pipe)})
      ]
    )
    (C {(end)})
  ]
)