AutoGen: autogen define

[ < ] | [ > ] |  | [ << ] | [ Up ] | [ >> ] |  |  |  |  | [Top] | [Contents] | [Index] | [ ? ]

## 5.21 define option (-D)

This is the "name to add to definition list" option.

This option has some usage constraints. It:

- may appear an unlimited number of times.
- is a member of the define class of options.

The AutoGen define names are used for the following purposes:

1. Sections of the AutoGen definitions may be enabled or disabled by using C-style #ifdef and #ifndef directives.
2. When defining a value for a name, you may specify the index for a particular value. That index may be a literal value, a define option or a value #define-d in the definitions themselves.
3. The name of a file may be prefixed with `$NAME/`. The `$NAME` part of the name string will be replaced with the define-d value for `NAME`.
4. When AutoGen is finished loading the definitions, the defined values are exported to the environment with, `putenv(3)`. These values can then be used in shell scripts with `${NAME}` references and in templates with `(getenv "NAME")`.
5. While processing a template, you may specify an index to retrieve a specific value. That index may also be a define-d value.

This document was generated by Bruce Korb on February 23, 2004 using texi2html