Breakpoints In Python - Debugging with GDB

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##### 23.2.2.19 Manipulating breakpoints using Python

Python code can manipulate breakpoints via the `gdb.Breakpoint` class.

— Method on Breakpoint: __init__ spec [type] [wp_class]

> Create a new breakpoint. spec is a string naming the location of the breakpoint, or an expression that defines a watchpoint. The contents can be any location recognized by the `break` command, or in the case of a watchpoint, by the `watch` command. The optional type denotes the breakpoint to create from the types defined later in this chapter. This argument can be either: `BP_BREAKPOINT` or `BP_WATCHPOINT`. type defaults to `BP_BREAKPOINT`. The optional wp_class argument defines the class of watchpoint to create, if type is defined as `BP_WATCHPOINT`. If a watchpoint class is not provided, it is assumed to be a WP_WRITE class.

The available watchpoint types represented by constants are defined in the `gdb` module:

`WP_READ`
  Read only watchpoint.

`WP_WRITE`
  Write only watchpoint.

`WP_ACCESS`
  Read/Write watchpoint.

— Method on Breakpoint: is_valid

> Return `True` if this `Breakpoint` object is valid, `False` otherwise. A `Breakpoint` object can become invalid if the user deletes the breakpoint. In this case, the object still exists, but the underlying breakpoint does not. In the cases of watchpoint scope, the watchpoint remains valid even if execution of the inferior leaves the scope of that watchpoint.

— Instance Variable of Breakpoint: enabled

> This attribute is `True` if the breakpoint is enabled, and `False` otherwise. This attribute is writable.

— Instance Variable of Breakpoint: silent

> This attribute is `True` if the breakpoint is silent, and `False` otherwise. This attribute is writable.

> Note that a breakpoint can also be silent if it has commands and the first command is `silent`. This is not reported by the `silent` attribute.

— Instance Variable of Breakpoint: thread

> If the breakpoint is thread-specific, this attribute holds the thread id. If the breakpoint is not thread-specific, this attribute is `None`. This attribute is writable.

— Instance Variable of Breakpoint: task

> If the breakpoint is Ada task-specific, this attribute holds the Ada task id. If the breakpoint is not task-specific (or the underlying language is not Ada), this attribute is `None`. This attribute is writable.

— Instance Variable of Breakpoint: ignore_count

> This attribute holds the ignore count for the breakpoint, an integer. This attribute is writable.

— Instance Variable of Breakpoint: number

> This attribute holds the breakpoint's number — the identifier used by the user to manipulate the breakpoint. This attribute is not writable.

— Instance Variable of Breakpoint: type

> This attribute holds the breakpoint's type — the identifier used to determine the actual breakpoint type or use-case. This attribute is not writable.

The available types are represented by constants defined in the `gdb` module:

`BP_BREAKPOINT`
  Normal code breakpoint.

`BP_WATCHPOINT`
  Watchpoint breakpoint.

`BP_HARDWARE_WATCHPOINT`
  Hardware assisted watchpoint.

`BP_READ_WATCHPOINT`
  Hardware assisted read watchpoint.

`BP_ACCESS_WATCHPOINT`
  Hardware assisted access watchpoint.

— Instance Variable of Breakpoint: hit_count

> This attribute holds the hit count for the breakpoint, an integer. This attribute is writable, but currently it can only be set to zero.

— Instance Variable of Breakpoint: location

> This attribute holds the location of the breakpoint, as specified by the user. It is a string. If the breakpoint does not have a location (that is, it is a watchpoint) the attribute's value is `None`. This attribute is not writable.

— Instance Variable of Breakpoint: expression

> This attribute holds a breakpoint expression, as specified by the user. It is a string. If the breakpoint does not have an expression (the breakpoint is not a watchpoint) the attribute's value is `None`. This attribute is not writable.

— Instance Variable of Breakpoint: condition

> This attribute holds the condition of the breakpoint, as specified by the user. It is a string. If there is no condition, this attribute's value is `None`. This attribute is writable.

— Instance Variable of Breakpoint: commands

> This attribute holds the commands attached to the breakpoint. If there are commands, this attribute's value is a string holding all the commands, separated by newlines. If there are no commands, this attribute is `None`. This attribute is not writable.