The name of a DLL that a package provides in UTF-8, or NULL. [allow-none]
a string containing the installation directory for package. The string is in the GLib file name encoding, i.e. UTF-8. The return value should be freed with g_free() when not needed any longer. If the function fails NULL is returned.
Warning g_win32_get_package_installation_directory has been deprecated since version 2.18 and should not be used in newly-written code. Pass the HMODULE of a DLL or EXE to g_win32_get_package_installation_directory_of_module() instead. Try to determine the installation directory for a software package. This function is deprecated. Use g_win32_get_package_installation_directory_of_module() instead. The use of package is deprecated. You should always pass NULL. A warning is printed if non-NULL is passed as package. The original intended use of package was for a short identifier of the package, typically the same identifier as used for GETTEXT_PACKAGE in software configured using GNU autotools. The function first looks in the Windows Registry for the value #InstallationDirectory in the key #HKLM\Software@package, and if that value exists and is a string, returns that. It is strongly recommended that packagers of GLib-using libraries for Windows do not store installation paths in the Registry to be used by this function as that interfers with having several parallel installations of the library. Enabling multiple installations of different versions of some GLib-using library, or GLib itself, is desirable for various reasons. For this reason it is recommeded to always pass NULL as package to this function, to avoid the temptation to use the Registry. In version 2.20 of GLib the package parameter will be ignored and this function won't look in the Registry at all. If package is NULL, or the above value isn't found in the Registry, but dll_name is non-NULL, it should name a DLL loaded into the current process. Typically that would be the name of the DLL calling this function, looking for its installation directory. The function then asks Windows what directory that DLL was loaded from. If that directory's last component is "bin" or "lib", the parent directory is returned, otherwise the directory itself. If that DLL isn't loaded, the function proceeds as if dll_name was NULL. If both package and dll_name are NULL, the directory from where the main executable of the process was loaded is used instead in the same way as above.