pdb3.4

pdb3.4 script [arg ...]

script
    The path to the Python script file that pdb3.4 should debug.

arg ...
    Optional arguments that will be passed to the script being debugged. These arguments are accessible within the script via sys.argv, just as they would be during normal execution.

The pdb3.4 command serves as an invocation of Python's interactive source code debugger, Pdb, specifically for Python version 3.4. Pdb is an integral part of Python's standard library and provides a powerful environment for analyzing and debugging Python programs. When invoked, pdb3.4 runs a specified Python script and pauses execution at the first line, allowing the user to step through code, set breakpoints, inspect variables, and evaluate expressions at runtime. It's a command-line tool, offering a prompt where various debugger commands can be entered. This allows developers to understand program flow, identify logical errors, and resolve issues efficiently without modifying the source code to add print statements. While Pdb is generally invoked using python -m pdb <script>, pdb3.4 provides a direct shortcut or alias for this operation using the Python 3.4 interpreter.

Version Specificity: pdb3.4 is tied to Python 3.4. Using it for scripts requiring newer Python features or libraries may lead to compatibility issues.

Interactive Nature: This is an interactive debugger. It requires user input to step through code or execute commands. It's not suitable for automated debugging in CI/CD pipelines without specific scripting for debugger interaction.

Limited External Options: The pdb3.4 command itself has very few direct command-line options. Most debugging functionality is accessed via commands entered at the interactive pdb prompt.

Installation: pdb3.4 might be an alias or a symlink provided by a system's Python 3.4 installation. It may not be available directly on all systems or require specific package installations.

Once inside the pdb prompt, users can type various commands to control execution and inspect the program state. Some common commands include:
h (help): Displays a list of available commands or help on a specific command.
l (list): Lists source code around the current line.
n (next): Continues execution until the next line in the current function is reached.
s (step): Executes the current line and stops at the first possible opportunity (can step into function calls).
c (continue): Continues execution until a breakpoint is hit or the program finishes.
b (breakpoint): Sets a breakpoint (e.g., b filename:lineno).
p (print): Evaluates and prints the value of an expression (e.g., p my_variable).
q (quit): Exits the debugger and terminates the program.
! (bang): Executes the remainder of the line as a Python statement in the context of the current stack frame.

The Pdb (Python Debugger) module has been a fundamental part of Python's standard library since its early versions. It provides a robust interactive debugging experience for Python developers. Python 3.4, released in 2014, included the Pdb module as standard, benefiting from ongoing improvements and bug fixes up to that version. The existence of a specific pdb3.4 command often indicates a system where multiple Python versions are installed side-by-side, and specific version-prefixed commands (like python3.4, pip3.4) are created to target particular interpreters. This allows developers to easily invoke the debugger for codebases tied to that specific Python 3.4 environment. While Pdb continues to evolve with newer Python versions, its core functionality and interactive commands have remained largely consistent over time.

python(1), gdb(1), valgrind(1)