diff options
Diffstat (limited to 'erts/doc/src/erlang.xml')
| -rw-r--r-- | erts/doc/src/erlang.xml | 234 |
1 files changed, 213 insertions, 21 deletions
diff --git a/erts/doc/src/erlang.xml b/erts/doc/src/erlang.xml index ba4e07b158..b40aae5d28 100644 --- a/erts/doc/src/erlang.xml +++ b/erts/doc/src/erlang.xml @@ -60,6 +60,14 @@ </desc> </datatype> <datatype> + <name>iovec()</name> + <desc> + <p>A list of binaries. This datatype is useful to use + together with <seealso marker="erl_nif#enif_inspect_iovec"> + <c>enif_inspect_iovec</c></seealso>.</p> + </desc> + </datatype> + <datatype> <name name="message_queue_data"></name> <desc> <p>See <seealso marker="#process_flag_message_queue_data"> @@ -181,6 +189,14 @@ </taglist> </desc> </datatype> + + <datatype> + <name name="dist_handle"></name> + <desc> + <p>An opaque handle identifing a distribution channel.</p> + </desc> + </datatype> + </datatypes> <funcs> @@ -424,6 +440,16 @@ Z = erlang:adler32_combine(X,Y,iolist_size(Data2)).</code> <seealso marker="#binary_to_atom/2"><c>binary_to_atom/2</c></seealso>, but the atom must exist.</p> <p>Failure: <c>badarg</c> if the atom does not exist.</p> + <note> + <p>Note that the compiler may optimize away atoms. For + example, the compiler will rewrite + <c>atom_to_list(some_atom)</c> to <c>"some_atom"</c>. If + that expression is the only mention of the atom + <c>some_atom</c> in the containing module, the atom will not + be created when the module is loaded, and a subsequent call + to <c>binary_to_existing_atom(<<"some_atom">>, utf8)</c> + will fail.</p> + </note> </desc> </func> @@ -1215,6 +1241,141 @@ end</code> </func> <func> + <name name="dist_ctrl_get_data" arity="1"/> + <fsummary>Get distribution channel data to pass to another node.</fsummary> + <desc> + <p> + Get distribution channel data from the local node that is + to be passed to the remote node. The distribution channel + is identified by <c><anno>DHandle</anno></c>. If no data + is available, the atom <c>none</c> is returned. One + can request to be informed by a message when more + data is available by calling + <seealso marker="erlang#dist_ctrl_get_data_notification/1"><c>erlang:dist_ctrl_get_data_notification(DHandle)</c></seealso>. + </p> + <note><p> + Only the process registered as distribution + controller for the distribution channel identified by + <c><anno>DHandle</anno></c> is allowed to call this + function. + </p></note> + <p> + This function is used when implementing an alternative + distribution carrier using processes as distribution + controllers. <c><anno>DHandle</anno></c> is retrived + via the callback + <seealso marker="erts:alt_dist#hs_data_f_handshake_complete"><c>f_handshake_complete</c></seealso>. + More information can be found in the documentation of + <seealso marker="erts:alt_dist#distribution_module">ERTS + User's Guide ➜ How to implement an Alternative Carrier + for the Erlang Distribution ➜ Distribution Module</seealso>. + </p> + </desc> + </func> + + <func> + <name name="dist_ctrl_get_data_notification" arity="1"/> + <fsummary>Request notification about available outgoing distribution channel data.</fsummary> + <desc> + <p> + Request notification when more data is available to + fetch using + <seealso marker="erlang#dist_ctrl_get_data/1"><c>erlang:dist_ctrl_get_data(DHandle)</c></seealso> + for the distribution channel identified by + <c><anno>DHandle</anno></c>. When more data is present, + the caller will be sent the message <c>dist_data</c>. + Once a <c>dist_data</c> messages has been sent, no + more <c>dist_data</c> messages will be sent until + the <c>dist_ctrl_get_data_notification/1</c> function has been called + again. + </p> + <note><p> + Only the process registered as distribution + controller for the distribution channel identified by + <c><anno>DHandle</anno></c> is allowed to call this + function. + </p></note> + <p> + This function is used when implementing an alternative + distribution carrier using processes as distribution + controllers. <c><anno>DHandle</anno></c> is retrived + via the callback + <seealso marker="erts:alt_dist#hs_data_f_handshake_complete"><c>f_handshake_complete</c></seealso>. + More information can be found in the documentation of + <seealso marker="erts:alt_dist#distribution_module">ERTS + User's Guide ➜ How to implement an Alternative Carrier + for the Erlang Distribution ➜ Distribution Module</seealso>. + </p> + </desc> + </func> + + <func> + <name name="dist_ctrl_input_handler" arity="2"/> + <fsummary>Register distribution channel input handler process.</fsummary> + <desc> + <p> + Register an alternate input handler process for the + distribution channel identified by <c><anno>DHandle</anno></c>. + Once this function has been called, <c><anno>InputHandler</anno></c> + is the only process allowed to call + <seealso marker="erlang#dist_ctrl_put_data/2"><c>erlang:dist_ctrl_put_data(DHandle, Data)</c></seealso> + with the <c><anno>DHandle</anno></c> identifing this distribution + channel. + </p> + <note><p> + Only the process registered as distribution + controller for the distribution channel identified by + <c><anno>DHandle</anno></c> is allowed to call this + function. + </p></note> + <p> + This function is used when implementing an alternative + distribution carrier using processes as distribution + controllers. <c><anno>DHandle</anno></c> is retrived + via the callback + <seealso marker="erts:alt_dist#hs_data_f_handshake_complete"><c>f_handshake_complete</c></seealso>. + More information can be found in the documentation of + <seealso marker="erts:alt_dist#distribution_module">ERTS + User's Guide ➜ How to implement an Alternative Carrier + for the Erlang Distribution ➜ Distribution Module</seealso>. + </p> + </desc> + </func> + + <func> + <name name="dist_ctrl_put_data" arity="2"/> + <fsummary>Pass data into the VM from a distribution channel.</fsummary> + <desc> + <p> + Deliver distribution channel data from a remote node to the + local node. + </p> + <note><p> + Only the process registered as distribution + controller for the distribution channel identified by + <c><anno>DHandle</anno></c> is allowed to call this + function unless an alternate input handler process + has been registered using + <seealso marker="erlang#dist_ctrl_input_handler/2"><c>erlang:dist_ctrl_input_handler(DHandle, InputHandler)</c></seealso>. + If an alternate input handler has been registered, only + the registered input handler process is allowed to call + this function. + </p></note> + <p> + This function is used when implementing an alternative + distribution carrier using processes as distribution + controllers. <c><anno>DHandle</anno></c> is retrived + via the callback + <seealso marker="erts:alt_dist#hs_data_f_handshake_complete"><c>f_handshake_complete</c></seealso>. + More information can be found in the documentation of + <seealso marker="erts:alt_dist#distribution_module">ERTS + User's Guide ➜ How to implement an Alternative Carrier + for the Erlang Distribution ➜ Distribution Module</seealso>. + </p> + </desc> + </func> + + <func> <name name="element" arity="2"/> <fsummary>Return the Nth element of a tuple.</fsummary> <type_desc variable="N">1..tuple_size(<anno>Tuple</anno>)</type_desc> @@ -1943,23 +2104,26 @@ os_prompt%</pre> <item>The runtime system exits with integer value <c><anno>Status</anno></c> as status code to the calling environment (OS). + <note> + <p>On many platforms, the OS supports only status + codes 0-255. A too large status code is truncated by clearing + the high bits.</p> + </note> </item> <tag>string()</tag> <item>An Erlang crash dump is produced with <c><anno>Status</anno></c> as slogan. Then the runtime system exits with status code <c>1</c>. - Note that only code points in the range 0-255 may be used - and the string will be truncated if longer than 200 characters. + The string will be truncated if longer than 200 characters. + <note> + <p>Before ERTS 9.1 (OTP-20.1) only code points in the range 0-255 + was accepted in the string. Now any unicode string is valid.</p> + </note> </item> <tag><c>abort</c></tag> <item>The runtime system aborts producing a core dump, if that is enabled in the OS. </item> </taglist> - <note> - <p>On many platforms, the OS supports only status - codes 0-255. A too large status code is truncated by clearing - the high bits.</p> - </note> <p>For integer <c><anno>Status</anno></c>, the Erlang runtime system closes all ports and allows async threads to finish their operations before exiting. To exit without such flushing, use @@ -2125,6 +2289,15 @@ os_prompt%</pre> </func> <func> + <name name="iolist_to_iovec" arity="1"/> + <fsummary>Converts an iolist to a iovec.</fsummary> + <desc> + <p>Returns an iovec that is made from the integers and binaries in + <c><anno>IoListOrBinary</anno></c>.</p> + </desc> + </func> + + <func> <name name="is_alive" arity="0"/> <fsummary>Check whether the local node is alive.</fsummary> <desc> @@ -2458,6 +2631,15 @@ os_prompt%</pre> but only if there already exists such atom.</p> <p>Failure: <c>badarg</c> if there does not already exist an atom whose text representation is <c><anno>String</anno></c>.</p> + <note> + <p>Note that the compiler may optimize away atoms. For + example, the compiler will rewrite + <c>atom_to_list(some_atom)</c> to <c>"some_atom"</c>. If + that expression is the only mention of the atom + <c>some_atom</c> in the containing module, the atom will not + be created when the module is loaded, and a subsequent call + to <c>list_to_existing_atom("some_atom")</c> will fail.</p> + </note> </desc> </func> @@ -3644,6 +3826,12 @@ RealSystem = system + MissedSystem</code> </item> <tag><c>{env, <anno>Env</anno>}</c></tag> <item> + <p> + Types:<br/> + <c><anno>Name</anno> = </c><seealso marker="kernel:os#type-env_var_name"><c>os:env_var_name()</c></seealso><br/> + <c><anno>Val</anno> = </c><seealso marker="kernel:os#type-env_var_value"><c>os:env_var_value()</c></seealso><c> | false</c><br/> + <c>Env = [{<anno>Name</anno>, <anno>Val</anno>}]</c> + </p> <p>Only valid for <c>{spawn, <anno>Command</anno>}</c>, and <c>{spawn_executable, <anno>FileName</anno>}</c>. The environment of the started process is extended using @@ -3658,7 +3846,13 @@ RealSystem = system + MissedSystem</code> exception is <c><anno>Val</anno></c> being the atom <c>false</c> (in analogy with <seealso marker="kernel:os#getenv/1"><c>os:getenv/1</c></seealso>, - which removes the environment variable.</p> + which removes the environment variable. + </p> + <p> + For information about encoding requirements, see documentation + of the types for <c><anno>Name</anno></c> and + <c><anno>Val</anno></c>. + </p> </item> <tag><c>{args, [ string() | binary() ]}</c></tag> <item> @@ -6293,17 +6487,24 @@ lists:map( <p><c><anno>MSAcc_Thread_Type</anno></c>s:</p> <taglist> <tag><c>scheduler</c></tag> - <item>The main execution threads that do most of the work.</item> + <item>The main execution threads that do most of the work. See + <seealso marker="erts:erl#+S">erl +S</seealso> for more details.</item> <tag><c>dirty_cpu_scheduler</c></tag> - <item>The threads for long running cpu intensive work.</item> + <item>The threads for long running cpu intensive work. See + <seealso marker="erts:erl#+SDcpu">erl +SDcpu</seealso> for more details.</item> <tag><c>dirty_io_scheduler</c></tag> - <item>The threads for long running I/O work.</item> + <item>The threads for long running I/O work. See + <seealso marker="erts:erl#+SDio">erl +SDio</seealso> for more details.</item> <tag><c>async</c></tag> <item>Async threads are used by various linked-in drivers (mainly the - file drivers) do offload non-CPU intensive work.</item> + file drivers) do offload non-CPU intensive work. See + <seealso marker="erts:erl#+async_thread_pool_size">erl +A</seealso> for more details.</item> <tag><c>aux</c></tag> <item>Takes care of any work that is not specifically assigned to a scheduler.</item> + <tag><c>poll</c></tag> + <item>Does the IO polling for the emulator. See + <seealso marker="erts:erl#+IOt">erl +IOt</seealso> for more details.</item> </taglist> <p>The following <c><anno>MSAcc_Thread_State</anno></c>s are available. All states are exclusive, meaning that a thread cannot be in two @@ -7860,15 +8061,6 @@ ok The return value will always be <c>false</c>, as the <c>elib_malloc</c> allocator has been removed.</p> </item> - <tag><marker id="system_info_eager_check_io"/> - <c>eager_check_io</c></tag> - <item> - <p>Returns the value of command-line flag - <seealso marker="erl#+secio"><c>+secio</c></seealso> in - <c>erl(1)</c>, which is either <c>true</c> or <c>false</c>. - For information about the different values, see the - documentation of the command-line flag.</p> - </item> <tag><c>ets_limit</c></tag> <item> <p>Returns the maximum number of ETS tables allowed. This |