4.11 Default Prefix

By default, configure sets the prefix for files it installs to `/usr/local'. The user of configure can select a different prefix using the `--prefix' and `--exec-prefix' options. There are two ways to change the default: when creating configure, and when running it.

Some software packages might want to install in a directory besides `/usr/local' by default. To accomplish that, use the AC_PREFIX_DEFAULT macro.

Macro: AC_PREFIX_DEFAULT (prefix)

Set the default installation prefix to prefix instead of `/usr/local'.

It may be convenient for users to have configure guess the installation prefix from the location of a related program that they have already installed. If you wish to do that, you can call AC_PREFIX_PROGRAM.

Macro: AC_PREFIX_PROGRAM (program)

If the user did not specify an installation prefix (using the `--prefix' option), guess a value for it by looking for program in PATH, the way the shell does. If program is found, set the prefix to the parent of the directory containing program; otherwise leave the prefix specified in `Makefile.in' unchanged. For example, if program is gcc and the PATH contains `/usr/local/gnu/bin/gcc', set the prefix to `/usr/local/gnu'.