Iwiseman: Created page with "=Introduction= This page is a page to remind me of how to use the cli debuggers for C++, Rails and Python =Debugging Commands Across Rails (rdbg), GDB, and Python (pdb)= Below are three separate MediaWiki tables — one for each debugger — covering: • Set breakpoint before starting • Set breakpoint inside debugger • Continue • Step • Step out • Print current source • Print/Evaluate expression ==GDB== {| class="wikitable" ! Action ! Command ! Notes |- |..."

2026-05-28T20:43:59Z

Created page with "=Introduction= This page is a page to remind me of how to use the cli debuggers for C++, Rails and Python =Debugging Commands Across Rails (rdbg), GDB, and Python (pdb)= Below are three separate MediaWiki tables — one for each debugger — covering: • Set breakpoint before starting • Set breakpoint inside debugger • Continue • Step • Step out • Print current source • Print/Evaluate expression ==GDB== {| class="wikitable" ! Action ! Command ! Notes |- |..."

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=Introduction=
This page is a page to remind me of how to use the cli debuggers for C++, Rails and Python

=Debugging Commands Across Rails (rdbg), GDB, and Python (pdb)=
Below are three separate MediaWiki tables — one for each debugger — covering:
• Set breakpoint before starting
• Set breakpoint inside debugger
• Continue
• Step
• Step out
• Print current source
• Print/Evaluate expression
==GDB==
{| class="wikitable"
! Action
! Command
! Notes
|-
| Set breakpoint before starting
| <code>gdb --args ./program</code> then <code>break file.c:LINE</code>
| Or <code>break main</code>.
|-
| Set breakpoint in debugger
| <code>break file.c:LINE</code>
| Can also break on functions.
|-
| Continue
| <code>continue</code> or <code>c</code>
| Runs until next breakpoint.
|-
| Step
| <code>step</code> or <code>s</code>
| Steps into function calls.
|-
| Step out
| <code>finish</code>
| Executes until current function returns.
|-
| Print current source
| <code>list</code> or <code>l</code>
| Shows source around current line.
|-
| Print/Evaluate expression
| <code>print expr</code>
| Evaluates C/C++ expressions.
|}
==Rails (rdbg)==
{| class="wikitable"
! Action
! Command
! Notes
|-
| Set breakpoint before starting
| <code>rdbg -n --command "break file.rb:LINE" -- bin/rails runner script.rb</code>
| Use <code>-n</code> to stop at the first breakpoint.
|-
| Set breakpoint in debugger
| <code>break file.rb:LINE</code>
| Or <code>break Class#method</code>.
|-
| Continue
| <code>continue</code> or <code>c</code>
| Runs until next breakpoint.
|-
| Step
| <code>step</code> or <code>s</code>
| Steps into method calls.
|-
| Step out
| <code>finish</code>
| Runs until current frame returns.
|-
| Print current source
| <code>list</code> or <code>l</code>
| Shows surrounding lines.
|-
| Print/Evaluate expression
| <code>p expr</code> or <code>pp expr</code>
| Ruby evaluation inside debugger.
|}
==Python (pdb)==
{| class="wikitable"
! Action
! Command
! Notes
|-
| Set breakpoint before starting
| <code>python -m pdb script.py</code> then <code>b file.py:LINE</code>
| Or insert <code>breakpoint()</code> in code.
|-
| Set breakpoint in debugger
| <code>b file.py:LINE</code>
| Or <code>b function_name</code>.
|-
| Continue
| <code>continue</code> or <code>c</code>
| Runs until next breakpoint.
|-
| Step
| <code>step</code> or <code>s</code>
| Steps into function calls.
|-
| Step out
| <code>return</code> or <code>r</code>
| Runs until current function returns.
|-
| Print current source
| <code>list</code> or <code>l</code>
| Shows surrounding lines.
|-
| Print/Evaluate expression
| <code>p expr</code> or <code>pp expr</code>
| Evaluates Python expressions.
|}

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