Date: Mon, 2 Sep 2019 21:04:48 +0200 From: Markus Wichmann <nullplan@....net> To: musl@...ts.openwall.com Subject: About those weak aliases Hi all, I'd like to know what those weak aliases are for in the many cases where they are used to define a public interface. Or, more to the point, by what criteria they are handed out, and by what logic the internal symbols are used. For instance, pthread_mutex_lock() et al. are weakly defined, but pthread_cond_wait() is not. Unlike pthread_cond_timedwait(), which is called from pthread_cond_wait() by the public symbol that might be interposed. Makes sense, since pthread_cond_wait() does not depend on mutex internals (pthread_cond_timedwait() does). I found no C standard function with a weak definition. But I did find crypt() being strongly defined, but it calls the internal (strong) definition of crypt_r(), rather than the weak one. So I thought maybe the C standard functions get strong definitions and all others get weak ones. But open(), close(), etc. are also defined strongly, while fdopen() gets a weak definition. And those are all in POSIX. Meanwhile, adjtime() gets a strong definition, as does getdents(), and those are Linux specialities. So yeah,I have so far failed to identify any rhyme or reason to these definitions. Can anyone help me? Ciao, Markus
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.