- Macro names that begin with uppercase letters are for your use. Names that begin with lowercase letters are reserved for sendmail's use. Twenty-seven special characters are also reserved by sendmail for use as operators. What happens if you try to define a macro whose name is another character, such as a tab or an underscore?
- What happens if you try to define a macro whose name is an operator?
- Using the
-d35.9 command-line switch, determine what happens if you define two macros, each with the same name.
- Any sendmail.cf command may be continued and extended by beginning the next line with a tab or a space. Using the
-d35.9 command-line switch, determine the effect of continuing a macro definition. For example,
D{FOO}something tab somethingmore
- The text value of a macro must immediately follow the name of that macro, with no intervening space. Can the text value contain arbitrary spaces or tabs?
- Using grep(1), find all the
D commands in your site's actual sendmail.cf file. If you find any that begin with a lowercase letter and that you haven't seen before, try looking them up in Defined Macros.