You use a watch condition to request a job breakpoint when the contents of a specified variable (or an expression that relates to a substring or an array element) is changed from its current value. Setting watch conditions is similar to setting conditional job breakpoints, with these important differences:
The debugger watches an expression or a variable through the contents of a storage address, computed at the time the watch condition is set. When the content at the storage address is changed from the value it had when the watch condition was set or when the last watch condition occurred, the program stops.
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