3.2 Using autoscan to Create `configure.ac'

The autoscan program can help you create and/or maintain a `configure.ac' file for a software package. autoscan examines source files in the directory tree rooted at a directory given as a command line argument, or the current directory if none is given. It searches the source files for common portability problems and creates a file `configure.scan' which is a preliminary `configure.ac' for that package, and checks a possibly existing `configure.ac' for completeness.

When using autoscan to create a `configure.ac', you should manually examine `configure.scan' before renaming it to `configure.ac'; it will probably need some adjustments. Occasionally, autoscan outputs a macro in the wrong order relative to another macro, so that autoconf produces a warning; you need to move such macros manually. Also, if you want the package to use a configuration header file, you must add a call to AC_CONFIG_HEADERS (see section 4.8 Configuration Header Files). You might also have to change or add some #if directives to your program in order to make it work with Autoconf (see section 3.3 Using ifnames to List Conditionals, for information about a program that can help with that job).

When using autoscan to maintain a `configure.ac', simply consider adding its suggestions. The file `autoscan.log' will contain detailed information on why a macro is requested.

autoscan uses several data files (installed along with Autoconf) to determine which macros to output when it finds particular symbols in a package's source files. These data files all have the same format: each line consists of a symbol, whitespace, and the Autoconf macro to output if that symbol is encountered. Lines starting with `#' are comments.

autoscan accepts the following options:

`--help'

`-h'

Print a summary of the command line options and exit.

`--version'

`-V'

Print the version number of Autoconf and exit.

`--verbose'

`-v'

Print the names of the files it examines and the potentially interesting symbols it finds in them. This output can be voluminous.

`--include=dir'

`-I dir'

Append dir to the include path. Multiple invocations accumulate.

`--prepend-include=dir'

`-B dir'

Prepend dir to the include path. Multiple invocations accumulate.