Redbug

https://hexdocs.pm/redbug/
Admin
Redbug is a project likely involved in compiler design, specifically focusing on components like...
Tokens:6,660
Snippets:76
Trust Score:9
Update:4 months ago
Show doc for...
Tokens:
Raw
### start(RTPs, Opts)

Source: https://hexdocs.pm/redbug/redbug.html

Starts a trace with the given RTPs and options.

```APIDOC
## start(RTPs, Opts)

### Description
Starts a trace with the given RTPs and options.

### Function Signature
start(RTPs :: list(), Opts :: map()) -> {Procs :: integer(), Functions :: integer()}
```

--------------------------------

### start(RTPs)

Source: https://hexdocs.pm/redbug/redbug.html

Starts a trace with the given RTPs, equivalent to start(RTPs, []).

```APIDOC
## start(RTPs)

### Description
Starts a trace with the given RTPs, equivalent to start(RTPs, []).

### Function Signature
start(RTPs)
```

--------------------------------

### start(Node, Cnf)

Source: https://hexdocs.pm/redbug/redbug_targ.html

Starts the redbug system with a specified node and configuration.

```APIDOC
## start(Node, Cnf)

### Description
Starts the redbug system with a specified node and configuration.

### Parameters
* **Node** (type) - Description
* **Cnf** (type) - Description
```

--------------------------------

### Basic Tracing with Redbug

Source: https://hexdocs.pm/redbug/readme.html

Start tracing a node, specifying the node name and the trace pattern. This example traces the 'erlang:demonitor' function.

```bash
$ redbug foo erlang:demonitor

% 14:19:29 <5270.91.0>(dead)
% erlang:demonitor(#Ref<5270.0.4.122>, [flush])

% 14:19:29 <5270.40.0>({erlang,apply,2})
% erlang:demonitor(#Ref<5270.0.4.130>, [flush])

% 14:19:29 <5270.40.0>({erlang,apply,2})
% erlang:demonitor(#Ref<5270.0.4.131>, [flush])

% 14:19:29 <5270.40.0>({erlang,apply,2})
% erlang:demonitor(#Ref<5270.0.4.132>, [flush])

redbug done, timeout - 4
```

--------------------------------

### Start Erlang Node for Tracing

Source: https://hexdocs.pm/redbug/index.html

Start an Erlang node that will be the target for Redbug tracing.

```bash
erl -sname foo
```

--------------------------------

### Start Redbug Trace

Source: https://hexdocs.pm/redbug/redbug.html

Starts a trace with specified RTPs and options. Returns the number of processes and functions traced.

```erlang
-spec start(RTPs :: list(), Opts :: map()) -> {Procs :: integer(), Functions :: integer()}.
```

--------------------------------

### Start Basic Call Trace

Source: https://hexdocs.pm/redbug/readme.html

Initiates a basic call trace for a specified function. The trace messages are printed to the console.

```erlang
1> redbug:start("erlang:demonitor").

  % 18:27:21 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203778.12948>)

  % 18:27:21 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203777.10938>, [flush])

  % 18:27:21 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203777.10939>, [flush])

  % 18:27:21 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203777.10940>, [flush])
  redbug done, timeout - 4
```

--------------------------------

### Basic Erlang Call Trace

Source: https://hexdocs.pm/redbug/index.html

Starts a basic trace for the 'erlang:demonitor' function. This snippet shows the function calls and their arguments as they occur.

```erlang
  1> redbug:start("erlang:demonitor").

  % 18:27:21 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203778.12948>)

  % 18:27:21 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203777.10938>, [flush])

  % 18:27:21 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203777.10939>, [flush])

  % 18:27:21 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203777.10940>, [flush])
  redbug done, timeout - 4

```

--------------------------------

### Trace erlang:demonitor Calls

Source: https://hexdocs.pm/redbug/index.html

Start tracing calls to erlang:demonitor on the target node. Redbug will output trace information and indicate when it's done.

```bash
$ redbug foo erlang:demonitor

% 14:19:29 <5270.91.0>(dead)
% erlang:demonitor(#Ref<5270.0.4.122>, [flush])

% 14:19:29 <5270.40.0>({erlang,apply,2})
% erlang:demonitor(#Ref<5270.0.4.130>, [flush])

% 14:19:29 <5270.40.0>({erlang,apply,2})
% erlang:demonitor(#Ref<5270.0.4.131>, [flush])

% 14:19:29 <5270.40.0>({erlang,apply,2})
% erlang:demonitor(#Ref<5270.0.4.132>, [flush])
redbug done, timeout - 4
```

--------------------------------

### Blocking Trace with Return Value

Source: https://hexdocs.pm/redbug/readme.html

Starts a trace in blocking mode, which pauses execution until the trace ends. It returns the stop reason and a list of collected trace messages.

```erlang
10> spawn(fun()->receive after 2000->ets:tab2list(inet_db) end end).
<0.540.0>
11> redbug:start("ets:tab2list(inet_db)",[blocking]).
{timeout,[{call,{{ets,tab2list,[inet_db]},<<>>},
                {<0.540.0>,{erlang,apply,2}},
                {15,50,43,776041}}]}
```

--------------------------------

### help()

Source: https://hexdocs.pm/redbug/redbug.html

Prints the help information for the redbug tool.

```APIDOC
## help()

### Description
Prints the help information for the redbug tool.

### Function Signature
help()
```

--------------------------------

### init()

Source: https://hexdocs.pm/redbug/redbug_targ.html

Initializes the redbug module. This function does not return any value.

```APIDOC
## init()

### Description
Initializes the redbug module. This function does not return any value.

### Method
(Implicitly a function call, not an HTTP method)

### Response
#### Success Response
- no_return()
```

--------------------------------

### main(Args)

Source: https://hexdocs.pm/redbug/redbug.html

The main function to execute redbug with provided arguments.

```APIDOC
## main(Args)

### Description
The main function to execute redbug with provided arguments.

### Function Signature
main(Args)
```

--------------------------------

### Initialize Redbug

Source: https://hexdocs.pm/redbug/redbug_targ.html

Initializes the redbug system. This function is non-returning.

```erlang
-spec init() -> no_return().
```

--------------------------------

### dtop()

Source: https://hexdocs.pm/redbug/redbug.html

Equivalent to calling dtop with an empty configuration.

```APIDOC
## dtop()

### Description
Equivalent to calling dtop with an empty configuration.

### Function Signature
dtop()
```

--------------------------------

### dtop(Cfg)

Source: https://hexdocs.pm/redbug/redbug.html

Calls dtop with a specified configuration.

```APIDOC
## dtop(Cfg)

### Description
Calls dtop with a specified configuration.

### Function Signature
dtop(Cfg)
```

--------------------------------

### Erlang Call Trace with Return Value and Stack

Source: https://hexdocs.pm/redbug/index.html

Traces 'erlang:demonitor', logs its return value, and prints the call stack. Note that only functions that will be returned to are shown due to tail call optimization.

```erlang
  3> redbug:start("erlang:demonitor->return,stack",[{msgs,2}]).
  {75,2}

  % 18:32:54 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203778.13012])
  %   redbug:block_a_little/0 
  %   redbug:start/2 
  %   erl_eval:do_apply/6 
  %   shell:exprs/7 
  %   shell:eval_exprs/7 
  %   shell:eval_loop/3 

```

--------------------------------

### scan(Str)

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Scans a string and returns a list of tokens. This is the initial step in the compilation process.

```APIDOC
## scan(Str)

### Description
Scans a string and returns a list of tokens.

### Method
Not applicable (function call)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Parameters
- **Str** (string()) - Description: The input string to be scanned.

### Response
#### Success Response
- **tokens** (tokens()) - Description: A list of tokens generated from the input string.

### Response Example
```json
{
  "tokens": [
    {"atom": 1, "integer": 1, "term": "value"} 
  ]
}
```
```

--------------------------------

### Trace Calls, Return Values, and Call Stack

Source: https://hexdocs.pm/redbug/readme.html

Traces function calls, return values, and the call stack. The call stack shows functions that will be returned to, considering tail call optimization.

```erlang
3> redbug:start("erlang:demonitor->return,stack",[{msgs,2}]).
  {75,2}

  % 18:32:54 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203778.13012>)
  %   redbug:block_a_little/0 
  %   redbug:start/2 
  %   erl_eval:do_apply/6 
  %   shell:exprs/7 
  %   shell:eval_exprs/7 
  %   shell:eval_loop/3 

```

--------------------------------

### Trace Process Messages and Sends

Source: https://hexdocs.pm/redbug/index.html

Trace both incoming messages and outgoing sends for a specific process. This provides a comprehensive view of communication involving the process.

```bash
$ redbug foo receive send -procs user_drv -msgs 2

% 17:43:28 <6071.31.0>(user_drv)
% <<< {#Port<6071.375>,{data,"a"}}

% 17:43:28 <6071.31.0>(user_drv)
% <6071.33.0>({group,server,3}) <<< {<6071.31.0>,{data,"a"}}
redbug done, msg_count - 2
```

--------------------------------

### compile(X)

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Compiles the input into a tp() type. This function likely performs the core compilation logic.

```APIDOC
## compile(X)

### Description
Compiles the input into a tp() type.

### Method
Not applicable (function call)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Parameters
- **X** (atom() | binary() | list()) - Description: The input to be compiled.

### Response
#### Success Response
- **tp** (tp()) - Description: The compiled output in tp() type format.

### Response Example
```json
{
  "tp": {
    "m_f_a": ["module", "function", 1],
    "args": [[], [[]]],
    "flags": []
  }
}
```
```

--------------------------------

### Run Redbug Escript

Source: https://hexdocs.pm/redbug/index.html

Execute the Redbug escript from the command line. Specify options, the target node, and trace patterns.

```bash
./_build/default/bin/redbug [-Opt Value [...]] TargetNode Trc [Trc...]
```

--------------------------------

### Trace and Print Return Value

Source: https://hexdocs.pm/redbug/index.html

Trace calls to erlang:demonitor and also print its return value. This requires setting a message count that accommodates both the call and the return.

```bash
$ redbug foo 'erlang:demonitor -> return' -msgs 2

% 14:23:47 <5276.115.0>(dead)
% erlang:demonitor(#Ref<5276.0.4.166>, [flush])

% 14:23:47 <5276.115.0>(dead)
% erlang:demonitor/2 -> true
redbug done, msg_count - 1
```

--------------------------------

### Erlang Call Trace with Return Value

Source: https://hexdocs.pm/redbug/index.html

Traces 'erlang:demonitor' and also prints its return value. The return value is logged as a separate message. Limited to 2 messages.

```erlang
  2> redbug:start("erlang:demonitor->return",[{msgs,2}]).
  {75,2}

  % 18:31:15 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203780.10535>)

  % 18:31:15 <0.188.0>({erlang,apply,2})
  % erlang:demonitor/1 -> true
  redbug done, msg_count - 1

```

--------------------------------

### Trace Return Value and Call Stack

Source: https://hexdocs.pm/redbug/index.html

Trace calls to erlang:demonitor, print its return value, and also display the call stack. This provides more detailed debugging information.

```bash
$ redbug foo 'erlang:demonitor -> return;stack' -msgs 2

% 14:24:43 <5276.121.0>(dead)
% erlang:demonitor(#Ref<5276.0.4.177>, [flush])
  shell:'-get_command/5-fun-0-'/1

% 14:24:43 <5276.121.0>(dead)
% erlang:demonitor/2 -> true
redbug done, msg_count - 1
```

--------------------------------

### Define args type

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Defines the 'args' type as a list or an underscore.

```erlang
-type args() :: list() | '_'.
```

--------------------------------

### stop()

Source: https://hexdocs.pm/redbug/redbug.html

Stops the current trace.

```APIDOC
## stop()

### Description
Stops the current trace.

### Function Signature
stop()
```

--------------------------------

### parse(Str)

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Parses a string into an Abstract Syntax Tree (AST). This function takes the output of the scan function (or a raw string) and structures it.

```APIDOC
## parse(Str)

### Description
Parses a string into an Abstract Syntax Tree (AST).

### Method
Not applicable (function call)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Parameters
- **Str** (string()) - Description: The input string to be parsed.

### Response
#### Success Response
- **AST** (ast()) - Description: The Abstract Syntax Tree representation of the input string.

### Response Example
```json
{
  "AST": [
    {"node": "expression", "children": []}
  ]
}
```
```

--------------------------------

### Trace Function Head Match

Source: https://hexdocs.pm/redbug/index.html

Trace calls to a specific function, like ets:tab2list, using a function head match. This allows for precise targeting of function calls.

```bash
$ redbug foo 'ets:tab2list(inet_db)' -msgs 2

% 17:45:48 <5276.40.0>({erlang,apply,2})
% ets:tab2list(inet_db)
redbug done, timeout - 1
```

--------------------------------

### Trace Function Calls and Return Values

Source: https://hexdocs.pm/redbug/readme.html

Traces function calls and also prints the return value as a separate message. It limits the trace to a specified number of messages.

```erlang
2> redbug:start("erlang:demonitor->return",[{msgs,2}]).
  {75,2}

  % 18:31:15 <0.188.0>({erlang,apply,2})
  % erlang:demonitor(#Ref<0.2419348116.2832203780.10535>)

  % 18:31:15 <0.188.0>({erlang,apply,2})
  % erlang:demonitor/1 -> true
  redbug done, msg_count - 1
```

--------------------------------

### Trace Process Messages

Source: https://hexdocs.pm/redbug/index.html

Trace incoming messages for a specific process, such as 'user_drv'. This helps in understanding inter-process communication.

```bash
$ redbug foo receive -procs user_drv -msgs 1

% 14:27:10 <6071.31.0>(user_drv)
% <<< {#Port<6071.375>,{data,"a"}}
redbug done, msg_count - 1
```

--------------------------------

### redbug_name(Opts)

Source: https://hexdocs.pm/redbug/redbug.html

Retrieves the name of the redbug instance with specified options.

```APIDOC
## redbug_name(Opts)

### Description
Retrieves the name of the redbug instance with specified options.

### Function Signature
redbug_name(Opts)
```

--------------------------------

### netload_test_()

Source: https://hexdocs.pm/redbug/redbug_targ.html

Performs a network load test. The specific return value or side effects are not detailed in the source.

```APIDOC
## netload_test_()

### Description
Performs a network load test. The specific return value or side effects are not detailed in the source.

### Method
(Implicitly a function call, not an HTTP method)
```

--------------------------------

### generate(AST)

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Generates a tp() type from an Abstract Syntax Tree (AST). This function might be used for code generation or intermediate representation.

```APIDOC
## generate(AST)

### Description
Generates a tp() type from an Abstract Syntax Tree (AST).

### Method
Not applicable (function call)

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Parameters
#### Path Parameters
None

#### Query Parameters
None

#### Request Body
None

### Parameters
- **AST** (ast()) - Description: The Abstract Syntax Tree to generate from.

### Response
#### Success Response
- **tp** (tp()) - Description: The generated output in tp() type format.

### Response Example
```json
{
  "tp": {
    "m_f_a": ["module", "function", 1],
    "args": [[], [[]]],
    "flags": []
  }
}
```
```

--------------------------------

### Define actions type

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Defines the 'actions' type as a list.

```erlang
-type actions() :: list().
```

--------------------------------

### parse_and_scan(_)

Source: https://hexdocs.pm/redbug/redbug_parser.html

Parses and scans input, which can be a function, a tuple representing a function, or a more complex structure. It returns a result of type yecc_ret().

```APIDOC
## parse_and_scan(_)

### Description
Parses and scans input, which can be a function, a tuple representing a function, or a more complex structure. It returns a result of type yecc_ret().

### Method
N/A (Function Signature)

### Parameters
#### Path Parameters
N/A

#### Query Parameters
N/A

#### Request Body
N/A

### Request Example
N/A

### Response
#### Success Response
- **return_value** (yecc_ret()) - The result of the parse and scan operation, which can be an error or an ok tuple.
```

--------------------------------

### Limit Trace Messages

Source: https://hexdocs.pm/redbug/index.html

Trace calls to erlang:demonitor but limit the output to a specific number of messages. This is useful for reducing noise in the trace.

```bash
$ redbug foo erlang:demonitor -msgs 1

% 14:22:09 <5276.103.0>(dead)
% erlang:demonitor(#Ref<5276.0.4.144>, [flush])
redbug done, msg_count - 1
```

--------------------------------

### Blocking Erlang Trace with Result

Source: https://hexdocs.pm/redbug/index.html

Uses the 'blocking' option to make redbug:start/2 block until the trace ends. It returns the stop reason and a list of collected trace messages.

```erlang
10> spawn(fun()->receive after 2000->ets:tab2list(inet_db) end end).
<0.540.0>
11> redbug:start("ets:tab2list(inet_db)",[blocking]).
{timeout,[{call,{{ets,tab2list,[inet_db]},<<>>},
                {<0.540.0>,{erlang,apply,2}},
                {15,50,43,776041}]}

```

--------------------------------

### get_rec_fields(Mod, Rec)

Source: https://hexdocs.pm/redbug/redbug_targ.html

Retrieves the fields associated with a specific record within a given module.

```APIDOC
## get_rec_fields(Mod, Rec)

### Description
Retrieves the fields associated with a specific record within a given module.

### Parameters
* **Mod** (type) - Description
* **Rec** (type) - Description
```

--------------------------------

### Generate function signature

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Specifies the signature for the 'generate' function, which takes an 'ast' type and returns a 'tp' type.

```erlang
-spec generate(ast()) -> tp().
```

--------------------------------

### stop(Target)

Source: https://hexdocs.pm/redbug/redbug.html

Stops a trace targeting a specific entity.

```APIDOC
## stop(Target)

### Description
Stops a trace targeting a specific entity.

### Function Signature
stop(Target)
```

--------------------------------

### Define flags type

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Defines the 'flags' type as a list.

```erlang
-type flags() :: list().
```

--------------------------------

### Define ast type

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Defines the 'ast' type as a tuple.

```erlang
-type ast() :: tuple().
```

--------------------------------

### Compile function signature

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Specifies the signature for the 'compile' function, which takes an atom, binary, or list and returns a 'tp' type.

```erlang
-spec compile(atom() | binary() | list()) -> tp().
```

--------------------------------

### Define m_f_a type

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Defines the 'm_f_a' type for module, function, and arguments.

```erlang
-type m_f_a() :: {atom(), atom() | '_', integer() | '_'}. 
```

--------------------------------

### Scan function signature

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Specifies the signature for the 'scan' function, which takes a string and returns 'tokens'.

```erlang
-spec scan(string()) -> tokens().
```

--------------------------------

### Parse function signature

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Specifies the signature for the 'parse' function, which takes a string and returns an 'ast' type.

```erlang
-spec parse(string()) -> ast().
```

--------------------------------

### parse(Tokens)

Source: https://hexdocs.pm/redbug/redbug_parser.html

Parses a list of tokens and returns a result of type yecc_ret(). This function is used for parsing structured data.

```APIDOC
## parse(Tokens)

### Description
Parses a list of tokens and returns a result of type yecc_ret(). This function is used for parsing structured data.

### Method
N/A (Function Signature)

### Parameters
#### Path Parameters
N/A

#### Query Parameters
N/A

#### Request Body
N/A

### Request Example
N/A

### Response
#### Success Response
- **return_value** (yecc_ret()) - The result of the parsing operation, which can be an error or an ok tuple.
```

--------------------------------

### format_error(Message)

Source: https://hexdocs.pm/redbug/redbug_parser.html

Formats an error message for display. It takes any type of message and returns a list of characters or a list.

```APIDOC
## format_error(Message)

### Description
Formats an error message for display. It takes any type of message and returns a list of characters or a list.

### Method
N/A (Function Signature)

### Parameters
#### Path Parameters
N/A

#### Query Parameters
N/A

#### Request Body
N/A

### Request Example
N/A

### Response
#### Success Response
- **return_value** (list() | [char()]) - The formatted error message.
```

--------------------------------

### Define guard type

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Defines the 'guard' type as a tuple or an underscore.

```erlang
-type guard() :: tuple() | '_'.
```

--------------------------------

### Define tp type

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Defines the 'tp' type, likely representing a compiled code structure.

```erlang
-type tp() :: {m_f_a(), [{args(), [guard()], actions()}], flags()}.
```

--------------------------------

### Define tokens type

Source: https://hexdocs.pm/redbug/redbug_compiler.html

Defines the 'tokens' type for lexical analysis results.

```erlang
-type tokens() :: [{atom(), integer(), term()} | {atom(), integer()}].
```

--------------------------------

### parse_and_scan Function Specification

Source: https://hexdocs.pm/redbug/redbug_parser.html

Specifies the type signature for the parse_and_scan function, which takes a specific tuple structure and returns a yecc_ret() type.

```erlang
-spec parse_and_scan({function() | {atom(), atom()}, [_]} | {atom(), atom(), [_]}) -> yecc_ret().
```

--------------------------------

### parse Function Specification

Source: https://hexdocs.pm/redbug/redbug_parser.html

Specifies the type signature for the parse function, which accepts a list of tokens and returns a yecc_ret() type.

```erlang
-spec parse(Tokens :: list()) -> yecc_ret().
```

--------------------------------

### yecc_ret Type Definition

Source: https://hexdocs.pm/redbug/redbug_parser.html

Defines the return type for parsing functions, indicating either an error or an OK result.

```erlang
-type yecc_ret() :: {error, _} | {ok, _}.
```

--------------------------------

### format_error Function Specification

Source: https://hexdocs.pm/redbug/redbug_parser.html

Specifies the type signature for the format_error function, which takes any type and returns a list of characters or a list.

```erlang
-spec format_error(any()) -> [char() | list()].
```
Tokens:
Raw