kumquat-buildroot/docs/manual/adding-packages-gettext.txt
Thomas Petazzoni 2289c34a19 docs/manual: update documentation about gettext handling
This commit updates the Buildroot manual regarding how gettext related
issues are handled, now that we have cases where the gettext package
should be selected even with glibc toolchains.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2014-08-18 10:36:31 +02:00

62 lines
2.2 KiB
Plaintext

// -*- mode:doc; -*-
// vim: set syntax=asciidoc:
=== Gettext integration and interaction with packages
Many packages that support internationalization use the gettext
library. Dependencies for this library are fairly complicated and
therefore, deserve some explanation.
The 'uClibc' C library doesn't implement gettext functionality;
therefore with this C library, a separate gettext must be compiled,
which is provided by the additional +libintl+ library, part of the
+gettext+ package.
On the other hand, the 'glibc' C library does integrate its own
gettext library functions, so it is not necessary to build a separate
+libintl+ library.
However, certain packages need some gettext utilities on the target,
such as the +gettext+ program itself, which allows to retrieve
translated strings, from the command line.
Additionally, some packages (such as +libglib2+) do require gettext
functions unconditionally, while other packages (in general, those who
support +--disable-nls+) only require gettext functions when locale
support is enabled.
Therefore, Buildroot defines two configuration options:
* +BR2_NEEDS_GETTEXT+, which is true as soon as the toolchain doesn't
provide its own gettext implementation
* +BR2_NEEDS_GETTEXT_IF_LOCALE+, which is true if the toolchain
doesn't provide its own gettext implementation and if locale support
is enabled
Packages that need gettext only when locale support is enabled should:
* use +select BR2_PACKAGE_GETTEXT if BR2_NEEDS_GETTEXT_IF_LOCALE+ in the
+Config.in+ file;
* use +$(if $(BR2_NEEDS_GETTEXT_IF_LOCALE),gettext)+ in the package
+DEPENDENCIES+ variable in the +.mk+ file.
Packages that unconditionally need gettext (which should be very rare)
should:
* use +select BR2_PACKAGE_GETTEXT if BR2_NEEDS_GETTEXT+ in the +Config.in+
file;
* use +$(if $(BR2_NEEDS_GETTEXT),gettext)+ in the package
+DEPENDENCIES+ variable in the +.mk+ file.
Packages that need the +gettext+ utilities on the target (should be
rare) should:
* use +select BR2_PACKAGE_GETTEXT+ in their +Config.in+ file,
indicating in a comment above that it's a runtime dependency only.
* not add any +gettext+ dependency in the +DEPENDENCIES+ variable of
their +.mk+ file.