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| -rw-r--r-- | doc/guix.texi | 44 |
1 files changed, 29 insertions, 15 deletions
diff --git a/doc/guix.texi b/doc/guix.texi index 38090cb9a3..97674d0fa7 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -7245,6 +7245,19 @@ A list of @code{search-path-specification} objects describing search-path environment variables honored by the package. @xref{Search Paths}, for more on search path specifications. +As for inputs, the distinction between @code{native-search-paths} and +@code{search-paths} only matters when cross-compiling. In a +cross-compilation context, @code{native-search-paths} applies +exclusively to native inputs whereas @code{search-paths} applies only to +host inputs. + +Packages such as cross-compilers care about target inputs---for +instance, our (modified) GCC cross-compiler has +@env{CROSS_C_INCLUDE_PATH} in @code{search-paths}, which allows it to +pick @file{.h} files for the target system and @emph{not} those of +native inputs. For the majority of packages though, only +@code{native-search-paths} makes sense. + @item @code{replacement} (default: @code{#f}) This must be either @code{#f} or a package object that will be used as a @dfn{replacement} for this package. @xref{Security Updates, grafts}, @@ -9408,7 +9421,7 @@ executable files to be installed: Many programs and libraries look for input data in a @dfn{search path}, a list of directories: shells like Bash look for executables in the command search path, a C compiler looks for @file{.h} files in its -header search path, and the Python interpreter looks for @file{.py} +header search path, the Python interpreter looks for @file{.py} files in its search path, the spell checker has a search path for dictionaries, and so on. @@ -9470,7 +9483,8 @@ variable must be defined to include all the @file{lib/python/3.9/site-packages} sub-directories encountered in its environment. (The @code{native-} bit means that, if we are in a cross-compilation environment, only native inputs may be added to the -search path.) In the NumPy example above, the profile where +search path; @pxref{package Reference, @code{search-paths}}.) +In the NumPy example above, the profile where @code{python} appears contains exactly one such sub-directory, and @env{GUIX_PYTHONPATH} is set to that. When there are several @file{lib/python/3.9/site-packages}---this is the case in package build @@ -9507,17 +9521,16 @@ to be found in @file{xml} sub-directories---nothing less. The search path specification looks like this: @lisp -(define libxml2 - (package - (name "libxml2") - ;; some fields omitted - (native-search-paths - (list (search-path-specification - (variable "XML_CATALOG_FILES") - (separator " ") - (files '("xml")) - (file-pattern "^catalog\\.xml$") - (file-type 'regular)))))) +(package + (name "libxml2") + ;; some fields omitted + (native-search-paths + (list (search-path-specification + (variable "XML_CATALOG_FILES") + (separator " ") + (files '("xml")) + (file-pattern "^catalog\\.xml$") + (file-type 'regular))))) @end lisp Worry not, search path specifications are usually not this tricky. @@ -9557,8 +9570,9 @@ In the libxml2 example above, we would match regular files; in the Python example, we would match directories. @item @code{file-pattern} (default: @code{#f}) -When true, this is a regular expression specifying files to be matched -@emph{within} the sub-directories specified by the @code{files} field. +This must be either @code{#f} or a regular expression specifying +files to be matched @emph{within} the sub-directories specified by the +@code{files} field. Again, the libxml2 example shows a situation where this is needed. @end table |