Changes between Version 9 and Version 10 of AppLibraries

Timestamp:

Jun 19, 2014, 9:17:21 AM (10 years ago)

Author:

davea

Comment:

--

AppLibraries

@@ -1 +1 @@
 = Dynamic library naming issues =
 
-Suppose your application uses a dynamic library, say '''example.dll'''.
+BOINC applications may include dynamically-loaded libraries
+('''.dll''' on Windows, '''.so''' on Unix).
+
+The search order for libraries is:
+
+ 1. The project directory
+ 1. The slot directory
+ 1. other directories
+
 Recall that [BoincFiles BOINC files are immutable].
-If you use the physical name '''example.dll'''
-there will be a problem if either
+Suppose that an app version uses a dynamic library
+with the physical name '''example.dll'''.
+There will be name collisions if either
 
  * You support multiple platforms (say, Win32 and Win64),
-   and there are different versions of '''example.dll''' for each platform.
+   and there are different versions of the library for each platform.
  * You need to update to new versions of the library.
 
-The easiest solution is:
- * Give the libraries physical names that encode the platform and version number,
-   e.g. '''example_win32_1_17.dll''' and '''example_win64_1_17.dll'''.
- * Use '''example.dll''' as the logical name.
-  To do this, use something like the following in your
-  [AppVersionNew#Theversiondescriptionfile version description file]:
+Name collisions can be avoided by giving the libraries physical names
+that encode the platform and version number,
+e.g. '''example_win32_1_17.dll''' and '''example_win64_1_17.dll'''.
+
+It may be inconvenient to rebuild the application to refer to these names
+rather than '''example.dll'''.
+To avoid this, include something like
 {{{
 ...
@@ -24 +34 @@
 ...
 }}}
-
-The '''copy_file''' flag tells the BOINC to copy the library to
-the application's runtime directory.
-
-== Avoiding name conflicts ==
-
-The search order for libraries is:
-
- 1. The project directory
- 1. The slot directory
- 1. other directories
-
-Hence if you use '''example.dll''' as a physical name in one app version,
-other app versions will use that library even if they
-use the above scheme.
-
-To avoid this problem, use logical names that don't conflict with physical names.
+in your [AppVersionNew#Theversiondescriptionfile version description file].
+This tells the BOINC client to copy the library to
+the application's slot directory with the name '''example.dll'''.
+When the application tries to load '''example.dll''',
+it will look in the project directory and not find it;
+then it will look in the slot directory and find it there.
 
 == .NET applications ==
@@ -46 +45 @@
 .NET does not use the current directory as a search path for dependencies.
 
-Our workaround is to install a handler for the AssemblyResolve event and use the
+A workaround is to install a handler for the !AssemblyResolve event and use the
 current directory (slot) to load the dependencies: