Intel XENIX 286 Programmers Guide (86) - Tenox.tc

adb: Program Debugger XENIX Programming
adb Va riables
adb automatically creates a set of its own variables whenever you start the debugger.
These variables are set to the addresses and sizes of various parts of the program file as
defined below.
d size of data
e entry address of the program
m execution type
n number of segments
t size of text
adb reads the program file to find the values for these variables. If the file does not
seem to be a program file, then adb leaves the values undefined.
You can use the current value of a variable in an expression by preceding the variable
name with a less-than sign ( variable-name
where expression is the value to be assigned to the variable, and variable-name must be
a single letter. For example, the assignment
Ox2000 >b
assigns the hexadecimal value "Ox2000" to the variable b.
You can display the value of all currently defined adb variables by using the $v
command. The command lists the variable names followed by their values in the current
format and displays any variable with a value that is not zero. If a variable also has a
nonzero segment value, the variable's value is displayed as an address; otherwise it is
displayed as a number.
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