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Breakpoints, watchpoints, and exceptions
In languages with exception handling (such as GNU C++), you can also set breakpoints where an exception is raised (see
In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
breakpoints in shared libraries before the executable is run.
A watchpoint is a special breakpoint that stops your program when the value of an
expression changes. You must use a different command to set watchpoints (see
You can arrange to have values from your program displayed automatically
whenever GDB stops at a breakpoint. See
GDB assigns a number to each breakpoint or watchpoint when you create it;
these numbers are successive integers starting with one. In many of the commands
for controlling various features of breakpoints, you use the breakpoint number to
say which breakpoint you want to change. Each breakpoint may be enabled or disabled; if disabled, it has no effect on your program until you enable it again.