---
name: "i"
section: "3erl"
platform: "linux"
package: "erlang-manpages"
version: "1:25.2.3+dfsg-1+deb12u4"
release: "Debian 12 (Bookworm)"
platforms: ["linux"]
url: "https://new.carta.tech/i/3erl"
---

# i(3erl)

Debugger/Interpreter Interface.

## NAME

i - Debugger/Interpreter Interface.

## DESCRIPTION

The *i* module provides short forms for some of the functions used by the graphical Debugger and some of the functions in module *int*, the Erlang interpreter.

This module also provides facilities for displaying status information about interpreted processes and break points.

It is possible to attach to interpreted processes by giving the corresponding process identity only. By default, an attachment window is displayed. Processes at other Erlang nodes can be attached manually or automatically.

By preference, these functions can be included in module *shell\_default*. By default, they are included in that module.

## EXPORTS

**im() -\> pid()**\

Starts a new graphical monitor. This is the Monitor window, the main window of Debugger. All the Debugger and interpreter functionality is accessed from the Monitor window. This window displays the status of all processes that have been or are executing interpreted modules.

**ii(AbsModules) -\> ok**\
 **ii(AbsModule) -\> {module, Module} \| error**\
 **ini(AbsModules) -\> ok**\
 **ini(AbsModule) -\> {module, Module} \| error**\

Types:

AbsModules = \[AbsModule\]\
 AbsModule = Module \| File\
\
  Module = atom()\
\
  File = string()\

Interprets the specified module(s). *ii/1* interprets the module(s) only at the current node, see int:i/1. *ini/1* interprets the module(s) at all known nodes, see int:ni/1.

**iq(AbsModule) -\> ok**\
 **inq(AbsModule) -\> ok**\

Types:

AbsModule = Module \| File\
\
  Module = atom()\
\
  File = string()\

Stops interpreting the specified module. *iq/1* stops interpreting the module only at the current node. *inq/1* stops interpreting the module at all known nodes.

**il() -\> ok**\

Makes a printout of all interpreted modules. Modules are printed together with the full path name of the corresponding source code file.

**ip() -\> ok**\

Prints the current status of all interpreted processes.

**ic() -\> ok**\

Clears information about processes executing interpreted code by removing all information about terminated processes.

**iaa(Flags) -\> true**\
 **iaa(Flags, Function) -\> true**\

Types:

Flags = \[init \| break \| exit\]\
 Function = {Module,Name,Args}\
\
  Module = Name = atom()\
\
  Args = \[term()\]\

Sets when and how to attach to a debugged process automatically, see int:auto\_attach/2. *Function* defaults to the standard function used by Debugger.

**ist(Flag) -\> true**\

Types:

Flag = all \| no\_tail \| false\

Sets how to save call frames in the stack, see int:stack\_trace/1.

**ia(Pid) -\> ok \| no\_proc**\

Types:

Pid = pid()\

Attaches to the debugged process *Pid*. An Attach Process window is opened for the process.

**ia(X,Y,Z) -\> ok \| no\_proc**\

Types:

X = Y = Z = int()\

Same as *ia(Pid)*, where *Pid* is the result of calling the shell function *pid(X,Y,Z)*.

**ia(Pid, Function) -\> ok \| no\_proc**\

Types:

Pid = pid()\
 Function = {Module,Name}\
\
  Module = Name = atom()\

Attaches to the debugged process *Pid*. The interpreter calls *spawn(Module, Name, \[Pid\])* (and ignores the result).

**ia(X,Y,Z, Function) -\> ok \| no\_proc**\

Types:

X = Y = Z = int()\
 Function = {Module,Name}\
\
  Module = Name = atom()\

Same as *ia(Pid, Function)*, where *Pid* is the result of calling the shell function *pid(X,Y,Z)*. An attached process is expected to call the unofficial function *int:attached(Pid)* and to be able to handle messages from the interpreter. For an example, see *dbg\_wx\_trace.erl*.

**ib(Module, Line) -\> ok \| {error, break\_exists}**\

Types:

Module = atom()\
 Line = int()\

Creates a breakpoint at *Line* in *Module*.

**ib(Module, Name, Arity) -\> ok \| {error, function\_not\_found}** \

Types:

Module = Name = atom()\
 Arity = int()\

Creates breakpoints at the first line of every clause of function *Module:Name/Arity*.

**ir() -\> ok**\

Deletes all breakpoints.

**ir(Module) -\> ok**\

Types:

Module = atom()\

Deletes all breakpoints in *Module*.

**ir(Module, Line) -\> ok**\

Types:

Module = atom()\
 Line = int()\

Deletes the breakpoint at *Line* in *Module*.

**ir(Module, Name, Arity) -\> ok \| {error, function\_not\_found}** \

Types:

Module = Name = atom()\
 Arity = int()\

Deletes the breakpoints at the first line of every clause of function *Module:Name/Arity*.

**ibd(Module, Line) -\> ok**\

Types:

Module = atom()\
 Line = int()\

Makes the breakpoint at *Line* in *Module* inactive.

**ibe(Module, Line) -\> ok**\

Types:

Module = atom()\
 Line = int()\

Makes the breakpoint at *Line* in *Module* active.

**iba(Module, Line, Action) -\> ok**\

Types:

Module = atom()\
 Line = int()\
 Action = enable \| disable \| delete\

Sets the trigger action of the breakpoint at *Line* in *Module* to *Action*.

**ibc(Module, Line, Function) -\> ok**\

Types:

Module = atom()\
 Line = int()\
 Function = {Module,Name}\
\
  Name = atom()\

Sets the conditional test of the breakpoint at *Line* in *Module* to *Function*.

The conditional test is performed by calling *Module:Name(Bindings)*, where *Bindings* is the current variable bindings. The function must return *true* (break) or *false* (do not break). To retrieve the value of a variable *Var*, use int:get\_binding(Var, Bindings).

**ipb() -\> ok**\

Prints all existing breakpoints.

**ipb(Module) -\> ok**\

Types:

Module = atom()\

Prints all existing breakpoints in *Module*.

**iv() -\> atom()**\

Returns the current version number of the interpreter. Same as the version number of the Debugger application.

**help() -\> ok**\

Prints help text.

## SEE ALSO

*[int(3erl)](/int/3erl.md)*