p (Program Trace)

p[n|t|z] [=addr][count]
 

The p command executes the instruction at a specified address and displays the current values of all the registers and flags (whatever the zd command has been set to). It then executes the default command string, if any. The p command is identical to the t (Trace Instructions) command, except that it automatically executes and returns from any calls or software interrupts it encounters. The t command always stops after executing into the call or interrupt, leaving execution control inside the called routine.

n

Suppresses the register display so just the assembly line is displayed. The suppression results only if the default command, zd, is set to a normal setting, r.

t or z

Allows trapped exceptions to resume at the original trap handler address without having to unhook the exception.

addr

Specifies the starting address at which to begin execution. If you omit the optional addr parameter, execution begins at the instruction pointed to by the CS and IP registers. Use the equal sign (=) only if you specify addr.

count

Specifies the number of instructions to execute before stopping and executing the default command string. The command executes the default command string for each instruction before executing the next.

The following example executes the instruction pointed to by the current CS and IP register values before it executes the default command string:

p
 

The following example executes the instruction at address CS:120 before it executes the default command string:

p=120

Program tracing through popf or popfd usually does not work.