HP UX Debugging Tools Creating Alias and Define Macros

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Creating Alias and Define Macros

You can use the alias and define commands to create two types of macros:

An alias macro serves as a synonym for one or more debugger commands. The debugger expands alias macros only when the macro is at the beginning of a command line, or when the macro follows a semicolon in a line of commands.

A de￿ne macro serves as a synonym for any string of text, including debugger commands. The debugger always expands a de￿ne macro no matter what position the macro occupies in a command line.

For example, consider the following series of commands:

alias show print
alias ali_X total	5
define def_X total
show ali_X
"ali_X" not found in current environment.
show def_X
total: 20
The alias commands create show as a synonym for the print command, and
ali_X as a synonym for the variable total. The define command also creates
a synonym for total , but gives it the name def_X.
The debugger does not expand ali_X in the command show ali_X since ali_X
does not appear at the beginning of the line and it does not follow a semicolon.
However, the debugger does expand def_X since de￿ne macros can appear
anywhere on the command line. Also, since the alias show appears ￿rst in both
of the last two command lines, the debugger expands show in both cases.
The debugger expands macros from left to righ t in the command line. Upon
￿nding a macro with argumen ts, the debugger inserts the argumen ts into the
macro de￿nition. Then the debugger rescans the command line, starting from
where it found the macro.
You can de￿ne macros in terms of other macros and nest them. Note that
macros cannot be recursiv e.

Using Debugger Commands 5-9