User`s guide

Chapter 6: Controlling Program Execution

The syntax of the trace command is:

trace variable Whenever the speciﬁed variable changes, dbx prints the old

and new values of that variable.

trace procedure

Prints the values of the parameters passed to the speciﬁed

procedure whenever your program calls it. Upon return,

dbx prints the return value.

trace [expression|variable] at line

Whenever your program reaches the speciﬁed line, dbx

prints the value of the variable if its value has changed.

If the expression is of type pointer, look at the data pointed

to and watch until it changes. If the expression is not of type

pointer, look at the 32 bits at that address (assume the

expression evaluates to an address).

trace [expression|variable] in procedure

Whenever the variable changes within the procedure, dbx

prints the old and new values of that variable.

If the expression is of type pointer, look at the data pointed

to and watch until it changes. If the expression is not of type

pointer, look at the 32 bits at that address (assume the

expression evaluates to an address).

trace [expression1|variable] at line if expression2

Prints the value of the variable (if changed) whenever your

program reaches the speciﬁed line and the given expression

is true.

If expression1 is of type pointer, look at the data pointed to

and watch until it changes. If expression1 is not of type

pointer, look at the 32 bits at that address (assume the

expression evaluates to an address).

trace [expression1|variable] in procedure if expression2

Whenever the variable changes within the procedure that

you specify, dbx prints the old and new values of that

variable, if the given expression is true.

If expression1 is of type pointer, look at the data pointed to