diff options
Diffstat (limited to 'erts/doc/src/erl_nif.xml')
| -rw-r--r-- | erts/doc/src/erl_nif.xml | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml index 9800a530f2..e8e7bd4a80 100644 --- a/erts/doc/src/erl_nif.xml +++ b/erts/doc/src/erl_nif.xml @@ -2583,7 +2583,7 @@ enif_map_iterator_destroy(env, &iter);</code> </func> <func> - <name><ret>enum ErlNifSelectReturn</ret> + <name><ret>int</ret> <nametext>enif_select(ErlNifEnv* env, ErlNifEvent event, enum ErlNifSelectFlags mode, void* obj, const ErlNifPid* pid, ERL_NIF_TERM ref)</nametext> </name> @@ -2626,36 +2626,36 @@ enif_map_iterator_destroy(env, &iter);</code> the event object. This safe way of closing event objects must be used even if all notifications have been received and no further calls to <c>enif_select</c> have been made.</p> - <p>Returns an integer where different bits indicate the outcome of the call:</p> + <p>Returns a non-negative value on success where the following bits can be set:</p> <taglist> - <tag><c>ERL_NIF_SELECT_ERROR</c></tag> - <item>The master error bit. It will always be set if the call failed for - any reason.</item> <tag><c>ERL_NIF_SELECT_STOP_CALLED</c></tag> <item>The stop callback was called directly by <c>enif_select</c>.</item> <tag><c>ERL_NIF_SELECT_STOP_SCHEDULED</c></tag> <item>The stop callback was scheduled to run on some other thread or later by this thread.</item> + </taglist> + <p>Returns a negative value if the call failed where the follwing bits can be set:</p> + <taglist> <tag><c>ERL_NIF_SELECT_INVALID_EVENT</c></tag> <item>Argument <c>event</c> is not a valid OS event object.</item> <tag><c>ERL_NIF_SELECT_FAILED</c></tag> <item>The system call failed to add the event object to the poll set.</item> </taglist> - <p>The return value from a successful call with <c>mode</c> as <c>ERL_NIF_SELECT_STOP</c>, - will contain either bit <c>ERL_NIF_SELECT_STOP_CALLED</c> or - <c>ERL_NIF_SELECT_STOP_SCHEDULED</c>.</p> <note> - <p>Always use bitwise AND to test the return value. New significant bits - may be added in future releases to give more detailed information for both - failed and successful calls. Do NOT use equallity tests like <c>==</c>, as - that may cause your application to stop working.</p> + <p>Use bitwise AND to test for specific bits in the return vaue. + New significant bits may be added in future releases to give more detailed + information for both failed and successful calls. Do NOT use equallity tests + like <c>==</c>, as that may cause your application to stop working.</p> <p>Example:</p> <code type="none"> -retval = enif_select(env, fd, ERL_NIF_SELECT_READ, resource, ref); -if (retval & ERL_NIF_SELECT_ERROR) { +retval = enif_select(env, fd, ERL_NIF_SELECT_STOP, resource, ref); +if (retval < 0) { /* handle error */ } /* Success! */ +if (retval & ERL_NIF_SELECT_STOP_CALLED) { + /* ... */ +} </code> </note> </desc> |