Using SCODB

Debugger variables

Use the var and unvar commands to set special debugger variables:

   var [name initial value]                        /* Create debugger variables */
   unvar [*|variables...]                          /* Remove debugger variables */

When debugging, certain values come up time and time again, and re-entering the value each time it is needed can be tedious and gives great opportunity for error.

Use the var command to create a variable with an initial value and type:

   debug0:1> var ino (struct inode *)D01401A0
   debug0:2> d $ino
   ...

Variables are also useful for counting iterations in breakpoint commands:

   debug0:3> var x 0
   debug0:4> $x
   0
   debug0:5> ++$x
   1
   debug0:5> ++$x
   2

The number of variables available is a configurable parameter. To reuse variables, unset them using the unvar command:

   debug0:9> unvar x
   debug0:10> $x
   Error: Unknown variable

unvar may be given the ``

'' argument, which clears all variables currently set.