Assignment To modify x, do print x=4
You can also use set. Or set variable. Continuing at a Different Address Use jump LOCATION to resume execution from a different point. Giving your Program a Signal You can give your program a signal. Useful if it stopped due to a signal but you want it to act as if it got no signal. Returning From a Function You can return from a function using return. Calling Program Functions If you do print EXPR it will evaluate the expression and return its value. Patching Binaries There is information on patching binaries. Compiling and injecting code in GDB
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