Shared library or something like this
Posted: Luglio 19th, 2008 | Author: packz | Filed under: Guide, Programmazione | Commenti disabilitati su Shared library or something like thisSto riscrivendo dei miei esempi di codice in C e ho varie routine di X11 da modificare in maniera tale da farle lavorare come librerie shared e poterle condividere facilmente tra i vari programmi che scrivo; visto che ogni volta mi incasino per farle funzionare perché non mi ricordo le flags da passare al compilatore/linker qui metto i miei tricks. Per adesso scrivo questo poi metto apposto tutto (sono reduce da una serata di alcol).
Dalla pagina di manuale di gcc(1)
-llibrary
-l library
Search the library named library when linking. (The second
alternative with the library as a separate argument is only for
POSIX compliance and is not recommended.)It makes a difference where in the command you write this option;
the linker searches and processes libraries and object files in the
order they are specified. Thus, foo.o -lz bar.o searches library z
after file foo.o but before bar.o. If bar.o refers to functions in
z, those functions may not be loaded.The linker searches a standard list of directories for the library,
which is actually a file named liblibrary.a. The linker then uses
this file as if it had been specified precisely by name.The directories searched include several standard system
directories plus any that you specify with -L.Normally the files found this way are library files—archive files
whose members are object files. The linker handles an archive file
by scanning through it for members which define symbols that have
so far been referenced but not defined. But if the file that is
found is an ordinary object file, it is linked in the usual
fashion. The only difference between using an -l option and
specifying a file name is that -l surrounds library with lib and .a
and searches several directories.
Ricordarsi che per passare opzioni direttamente al linker si necessita della flag -Wl,<Opzione>,<valore>. Molto comoda l’opzione -rpath (vedi ld(1)).