# TODO(csilvers): it would be better to actually try to link against# -pthreads, to make sure it defines these methods, but that may be# too hard, since pthread support is really tricky.# Check for support for pthread_rwlock_init() etc.# These aren't posix, but are widely supported. To get them on linux,# you need to define _XOPEN_SOURCE first, so this check assumes your# application does that.## Note: OS X (as of 6/1/06) seems to support pthread_rwlock, but# doesn't define PTHREAD_RWLOCK_INITIALIZER. Therefore, we don't test# that particularly macro. It's probably best if you don't use that# macro in your code either.AC_DEFUN([AC_RWLOCK],[AC_CACHE_CHECK(support for pthread_rwlock_* functions,ac_rwlock,[AC_LANG_SAVE AC_LANG_C AC_TRY_COMPILE([#define _XOPEN_SOURCE 500 #include <pthread.h>], [pthread_rwlock_t l; pthread_rwlock_init(&l, NULL); pthread_rwlock_rdlock(&l); return 0;], ac_rwlock=yes, ac_rwlock=no) AC_LANG_RESTORE])if test "$ac_rwlock" = yes; then AC_DEFINE(HAVE_RWLOCK,1,[define if the compiler implements pthread_rwlock_*])fi])
