In Asterisk, a macro is a special kind of context which can be expanded within the definition of another context. Its name must begin with “macro-”. A macro is expanded by using the Macro command.

All the lines of the macro definition should only use the s extension; the actual extension will come from the line in the calling context on which the macro is expanded.

Within the macro definition, use the variable substitution ${MACRO_EXTEN} to refer to the actual extension.