GDB, the GNU Project debugger, allows you to see what is going on `inside' another program while it executes -- or what another program was doing at the moment it crashed.
GDB can
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make your program stop on specified conditions
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, examine what has happened, when your program has stopped
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, and even change things in your program, so you can experiment with correcting the effects of one bug and go on to learn about another.
Please refer to the official GDB documentation for all the information on how to use this tool.
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