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skills/debugging-with-tools/resources/debugger-reference.md

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+## Debugger Quick Reference
+
+### Automated Debugging (Claude CAN run these)
+
+#### lldb Batch Mode
+
+```bash
+# One-shot command to inspect variable at breakpoint
+lldb -o "breakpoint set --file main.rs --line 42" \
+     -o "run" \
+     -o "frame variable my_var" \
+     -o "quit" \
+     -- target/debug/myapp 2>&1
+
+# With script file for complex debugging
+cat > debug.lldb <<'EOF'
+breakpoint set --file main.rs --line 42
+run
+frame variable
+bt
+up
+frame variable
+quit
+EOF
+
+lldb -s debug.lldb target/debug/myapp 2>&1
+```
+
+#### strace (Linux - system call tracing)
+
+```bash
+# See which files program opens
+strace -e trace=open,openat cargo run 2>&1 | grep -v "ENOENT"
+
+# Find network activity
+strace -e trace=network cargo run 2>&1
+
+# All syscalls with time
+strace -tt cargo test some_test 2>&1
+```
+
+#### dtrace (macOS - dynamic tracing)
+
+```bash
+# Trace function calls
+sudo dtrace -n 'pid$target:myapp::entry { printf("%s", probefunc); }' -p <PID>
+```
+
+### Interactive Debugging (USER runs these, Claude guides)
+
+**These require interactive terminal - Claude provides commands, user runs them**
+
+### lldb (Rust, Swift, C++)
+
+```bash
+# Start debugging
+lldb target/debug/myapp
+
+# Set breakpoints
+(lldb) breakpoint set --file main.rs --line 42
+(lldb) breakpoint set --name my_function
+
+# Run
+(lldb) run
+(lldb) run arg1 arg2
+
+# When paused:
+(lldb) frame variable              # Show all locals
+(lldb) print my_var                # Print specific variable
+(lldb) bt                          # Backtrace (stack)
+(lldb) up / down                   # Navigate stack
+(lldb) continue                    # Resume
+(lldb) step / next                 # Step into / over
+(lldb) finish                      # Run until return
+```
+
+### Browser DevTools (JavaScript)
+
+```javascript
+// In code:
+debugger; // Execution pauses here
+
+// In DevTools:
+// - Sources tab → Add breakpoint by clicking line number
+// - When paused:
+//   - Scope panel: See all variables
+//   - Watch: Add expressions to watch
+//   - Call stack: Navigate callers
+//   - Step over (F10), Step into (F11)
+```
+
+### gdb (C, C++, Go)
+
+```bash
+# Start debugging
+gdb ./myapp
+
+# Set breakpoints
+(gdb) break main.c:42
+(gdb) break myfunction
+
+# Run
+(gdb) run
+
+# When paused:
+(gdb) print myvar
+(gdb) info locals
+(gdb) backtrace
+(gdb) up / down
+(gdb) continue
+(gdb) step / next
+```
+