-D name=definitionIf you are invoking the preprocessor from a shell or shell-like program you may need to use the shell's quoting syntax to protect characters such as spaces that have a meaning in the shell syntax.
If you wish to define a function-like macro on the command line, write its argument list with surrounding parentheses before the equals sign (if any). Parentheses are meaningful to most shells, so you will need to quote the option. With sh and csh, -D'name(args...)=definition' works.
def_dpf = 'dpf(a...)=printk(KERN_ALERT a)'
dpf("current value=%d\n",var);
Even manual says sh and csh can works with that definition, bash should support that machanism, I guess. How should I do? Any suggestion?error: ‘Da’ undeclared (first use in this function)