diff options
| -rw-r--r-- | build2/b.cli | 48 |
1 files changed, 40 insertions, 8 deletions
diff --git a/build2/b.cli b/build2/b.cli index dff707f..532688f 100644 --- a/build2/b.cli +++ b/build2/b.cli @@ -26,10 +26,10 @@ namespace build2 \h|DESCRIPTION| - The \cb{build2} driver executes a set of meta-operations on operations on - targets according to the build specification, or \i{buildspec} for short. - This process can be controlled by specifying driver <options> and build - system <variables>. + The \cb{build2} build system driver executes a set of meta-operations on + operations on targets according to the build specification, or + \i{buildspec} for short. This process can be controlled by specifying + driver <options> and build system <variables>. Note that <options>, <variables>, and <buildspec> fragments can be specified in any order. To avoid treating an argument that starts with @@ -130,7 +130,7 @@ namespace build2 ./: */ \ - In the above example, we assumed that the \cb{build2} driver was able to + In the above example, we assumed that the build system driver was able to determine the association between \cb{out_base} and \cb{src_base}. In case \cb{src_base} and \cb{out_base} are not the same directory, this is achieved in one of two ways: the \cb{config} module (which implements the @@ -645,12 +645,44 @@ namespace build2 bool --version {"Print version and exit."} }; - "\h|EXIT STATUS| + " + \h|DEFAULT OPTIONS FILES| + + Instead of having a separate config file format for tool configuration, the + \cb{build2} toolchain uses \i{default options files} which contain the same + options as what can be specified on the command line. The default options + files are like options files that one can specify with \cb{--options-file} + except that they are loaded by default. + + The default options files for the build system driver are called + \cb{b.options} and are searched for in the \cb{.build2/} subdirectory of the + home directory and in the system directory (for example, \cb{/etc/build2/}) + if configured. + + Once the search is complete, the files are loaded in the reverse order, that + is, beginning from the system directory (if any), followed by the home + directory, and finishing off with the options specified on the command line. + In other words, the files are loaded from the more generic to the more + specific with the command line options having the ability to override any + values specified in the default options files. + + If a default options file contains \cb{--no-default-options}, then the + search is stopped at the directory containing this file and no outer files + are loaded. If this option is specified on the command line, then none of + the default options files are searched for or loaded. + + An additional directory containing default options files can be specified + with \cb{--default-options}. Its configuration files are loaded after the + home directory. + + The order in which default options files are loaded is traced at the + verbosity level 3 (\cb{-V} option) or higher. + + \h|EXIT STATUS| Non-zero exit status is returned in case of an error. - " - "\h|ENVIRONMENT| + \h|ENVIRONMENT| The \cb{HOME} environment variable is used to determine the user's home directory. If it is not set, then \cb{getpwuid(3)} is used instead. This |