On Thursday 17 August 2017 10:54:31 Graeme Geldenhuys wrote: > On 2017-08-17 07:18, Martin Schreiber wrote: > > I don't understand why FPC uses the version-less library > > names instead of the mayor version names where the bindings are made for. > > Maybe a misunderstanding happened at ancient times... > > No, they are simply following the guidelines of Unix-type systems - > doing everything correctly by the book.
A hypothetical example: - You make a pascal bindings file for the "greatlibrary" version 1.0. - You set the library name in the bindings pascal file "great.pas" to "great" as Unix-type systems guidelines command. - In your system great-devel package of the version 1.0.1 is installed, you have the c-header *.h files of libgreat 1.0.1 and the links libgreat.so -> libgreat.so.1 -> libgreat.so.1.0.1. - The SONAME of libgreat.so.1.0.1 is libgreat.so.1 - You compile and run the application, libgreat.so.1 -> libgreat.so.1.0.1 is loaded, all is OK. Now you give the source of the application to a colleague who has installed the newer but incompatible "greatlibrary" version 2.0.3 including the devel package. - He has the c-header *.h files of libgreat 2.0.3 and links libgreat.so -> libgreat.so.2 -> libgreat.so.2.0.3. - The SONAME of libgreat.so.2.0.3 is libgreat.so.2 - He compiles your program, the linker links libgreat.so -> libgreat.so.2 -> libgreat.so.2.0.3 and stores the SONAME libgreat.so.2 (remember, libgreat.so.2 and libgreat.so.1 are *not* compatible). Now there are two possibilities, maybe the function names in libgreat.pas did not change between version 1 and 2 -> the program compiles but crashes because of changed parameters or other incompatibilities. Or it does not compile and then he needs to install version 1 of "greatlibrary" and deinstall great-devel-2.0.3 and install great-devel-1.0.1 or change manually libgreat.so -> libgreat.so.2 to libgreat.so -> libgreat.so.1 temporarily. This also must be done in first case in order to produce a working application. The difference between a FPC bindings unit and a Unix C-header *.h file is that the *.h file is *included* in the devel-package and thus matches the installed version, the pascal file is not included but in a separate package or more likely taken from the FPC tar archive by the FPC install script because FPC Linux/FreeBSD-packages usually are too old or one wants to use a FPC version from SVN. So the "guidelines for Unix-type systems" are not appropriate for Free Pascal C-library binding units IMHO. Martin ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ mseide-msegui-talk mailing list mseide-msegui-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mseide-msegui-talk
