GDB The GNU DeBugger

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GDB - The GNU DeBugger

• To run gdb (a text-based debugger)
• gdb ltprogram filegt ltcore filegt
• ltprogram filegt Executable program file
• ltcore filegt Crashed programs core dump
• You must compile with -g for debug information!
• Within gdb
• Running gdb
• run ltargsgt Run program with arguments ltargsgt
• quit Quit the gdb debugger
• help lttopicgt Access gdbs internal help
• Examining program state
• info localsargs Prints out info on local
  variablesargs
• backtraceltngt Prints the top ltngt frames on the
  stack
• print ltexprgt Print out ltexprgt

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GDB continued

• Controlling program flow
• step Step one line, entering called functions
• next Step one line, skipping called functions
• finish Finish the current function and print the
  return value
• Controlling program flow with breakpoints
• continue Continue execution (after a stop)
• breakltwheregt Set a breakpoint
• delete ltnumsgt Deletes breakpoints by number
• rwatch ltexprgt Sets a watchpoint, which will
  break when ltexprgt is written to or read
• Modifying program state
• set ltnamegt ltexprgt Set a variable to ltexprgt
• jump ltwheregt Resume program execution at ltwheregt