diff options
Diffstat (limited to 'erts/doc/src/erl_nif.xml')
| -rw-r--r-- | erts/doc/src/erl_nif.xml | 146 |
1 files changed, 130 insertions, 16 deletions
diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml index ef3cdb89e9..8a9ae58e99 100644 --- a/erts/doc/src/erl_nif.xml +++ b/erts/doc/src/erl_nif.xml @@ -367,6 +367,8 @@ return term;</code> <c>enif_ioq_deq()</c></seealso></item> <item><seealso marker="#enif_ioq_peek"> <c>enif_ioq_peek()</c></seealso></item> + <item><seealso marker="#enif_ioq_peek_head"> + <c>enif_ioq_peek_head()</c></seealso></item> <item><seealso marker="#enif_inspect_iovec"> <c>enif_inspect_iovec()</c></seealso></item> <item><seealso marker="#enif_free_iovec"> @@ -538,7 +540,7 @@ int writeiovec(ErlNifEnv *env, ERL_NIF_TERM term, ERL_NIF_TERM *tail, have to wait for a very long time. Blocking multi-scheduling, that is, calling <seealso marker="erlang#system_flag_multi_scheduling"> <c>erlang:system_flag(multi_scheduling, block)</c></seealso>, can - also take a very long time to complete. This becaue all ongoing + also take a very long time to complete. This is because all ongoing dirty operations on all dirty schedulers must complete before the block operation can complete.</p> <p>Many operations communicating with a process executing a @@ -588,7 +590,7 @@ int writeiovec(ErlNifEnv *env, ERL_NIF_TERM term, ERL_NIF_TERM *tail, <c>unload</c> is called to release the library. All are described individually below.</p> <p>The fourth argument <c>NULL</c> is ignored. It - was earlier used for the deprectated <c>reload</c> callback + was earlier used for the deprecated <c>reload</c> callback which is no longer supported since OTP 20.</p> <p>If compiling a NIF for static inclusion through <c>--enable-static-nifs</c>, you must define <c>STATIC_ERLANG_NIF</c> @@ -807,7 +809,7 @@ typedef void ErlNifResourceDtor(ErlNifEnv* env, void* obj);</code> <tag><marker id="ErlNifResourceDown"/><c>ErlNifResourceDown</c></tag> <item> <code type="none"> -typedef void ErlNifResourceDown(ErlNifEnv* env, void* obj, const ErlNifPid* pid, const ErlNifMonitor* mon);</code> +typedef void ErlNifResourceDown(ErlNifEnv* env, void* obj, ErlNifPid* pid, ErlNifMonitor* mon);</code> <p>The function prototype of a resource down function, called on the behalf of <seealso marker="#enif_monitor_process"> enif_monitor_process</seealso>. <c>obj</c> is the resource, <c>pid</c> @@ -873,7 +875,7 @@ typedef enum { <item> <p>An enumeration of the properties that can be requested from <seealso marker="#enif_make_unique_integer"> - <c>enif_unique_integer</c></seealso>. + <c>enif_make_unique_integer</c></seealso>. For default properties, use value <c>0</c>.</p> <taglist> <tag><c>ERL_NIF_UNIQUE_POSITIVE</c></tag> @@ -972,6 +974,10 @@ typedef struct { <seealso marker="#enif_make_binary"><c>enif_make_binary</c></seealso>. An allocated (and owned) <c>ErlNifBinary</c> can be kept between NIF calls.</p> + <p>If you do not need to reallocate or keep the data alive across NIF + calls, consider using <seealso marker="#enif_make_new_binary"> + <c>enif_make_new_binary</c></seealso> instead as it will allocate + small binaries on the process heap when possible.</p> <p>Returns <c>true</c> on success, or <c>false</c> if allocation fails.</p> </desc> @@ -1098,6 +1104,16 @@ typedef struct { </func> <func> + <name><ret>char*</ret> + <nametext>enif_cond_name(ErlNifCond* cnd)</nametext></name> + <fsummary></fsummary> + <desc> + <p>Same as <seealso marker="erl_driver#erl_drv_cond_name"> + <c>erl_drv_cond_name</c></seealso>.</p> + </desc> + </func> + + <func> <name><ret>void</ret> <nametext>enif_cond_signal(ErlNifCond *cnd)</nametext></name> <fsummary></fsummary> @@ -1230,6 +1246,18 @@ typedef struct { </func> <func> + <name><ret>int</ret><nametext>enif_fprintf(FILE *stream, const char *format, ...)</nametext></name> + <fsummary>Format strings and Erlang terms.</fsummary> + <desc> + <p>Similar to <c>fprintf</c> but this format string also accepts + <c>"%T"</c>, which formats Erlang terms.</p> + <p>This function was originally intenden for debugging purpose. It is not + recommended to print very large terms with <c>%T</c>. The function may + change <c>errno</c>, even if successful.</p> + </desc> + </func> + + <func> <name><ret>void</ret><nametext>enif_free(void* ptr)</nametext></name> <fsummary>Free dynamic memory.</fsummary> <desc> @@ -1264,7 +1292,7 @@ typedef struct { ErlNifIOVec *iovec = NULL; size_t max_elements = 128; ERL_NIF_TERM tail; -if (!enif_inspect_iovec(NULL, max_elements, term, &tail, iovec)) +if (!enif_inspect_iovec(NULL, max_elements, term, &tail, &iovec)) return 0; // Do things with the iovec @@ -1683,8 +1711,7 @@ enif_inspect_iovec(env, max_elements, term, &tail, &iovec); <fsummary>Peek inside the IO Queue</fsummary> <desc> <p>Get the I/O queue as a pointer to an array of <c>SysIOVec</c>s. - It also returns the number of elements in <c>iovlen</c>. - This is the only way to get data out of the queue.</p> + It also returns the number of elements in <c>iovlen</c>.</p> <p>Nothing is removed from the queue by this function, that must be done with <seealso marker="#enif_ioq_deq"><c>enif_ioq_deq</c></seealso>.</p> <p>The returned array is suitable to use with the Unix system @@ -1693,6 +1720,21 @@ enif_inspect_iovec(env, max_elements, term, &tail, &iovec); </func> <func> + <name><ret>int</ret> + <nametext>enif_ioq_peek_head(ErlNifEnv *env, ErlNifIOQueue *q, size_t *size, ERL_NIF_TERM *bin_term)</nametext></name> + <fsummary>Peek the head of the IO Queue.</fsummary> + <desc> + <p>Get the head of the IO Queue as a binary term.</p> + <p>If <c>size</c> is not <c>NULL</c>, the size of the head is placed + there.</p> + <p>Nothing is removed from the queue by this function, that must be done + with <seealso marker="#enif_ioq_deq"><c>enif_ioq_deq</c></seealso>.</p> + <p>Returns <c>true</c> on success, or <c>false</c> if the queue is + empty.</p> + </desc> + </func> + + <func> <name><ret>size_t</ret> <nametext>enif_ioq_size(ErlNifIOQueue *q)</nametext></name> <fsummary>Get the current size of the IO Queue</fsummary> @@ -2143,6 +2185,20 @@ enif_inspect_iovec(env, max_elements, term, &tail, &iovec); </func> <func> + <name><ret>int</ret> + <nametext>enif_make_map_from_arrays(ErlNifEnv* env, ERL_NIF_TERM keys[], + ERL_NIF_TERM values[], size_t cnt, ERL_NIF_TERM *map_out)</nametext></name> + <fsummary>Make map term from the given keys and values.</fsummary> + <desc> + <p>Makes a map term from the given keys and values.</p> + <p>If successful, this function sets <c>*map_out</c> to the new map and + returns <c>true</c>. Returns <c>false</c> there are any duplicate + keys.</p> + <p>All keys and values must belong to <c>env</c>.</p> + </desc> + </func> + + <func> <name><ret>unsigned char *</ret><nametext>enif_make_new_binary(ErlNifEnv* env, size_t size, ERL_NIF_TERM* termp)</nametext></name> <fsummary>Allocate and create a new binary term.</fsummary> @@ -2216,7 +2272,7 @@ enif_inspect_iovec(env, max_elements, term, &tail, &iovec); <seealso marker="#enif_get_resource"><c>enif_get_resource</c></seealso>.</p> </item> <item> - <p>A resoure term can be serialized with <c>term_to_binary</c> and later + <p>A resource term can be serialized with <c>term_to_binary</c> and later be fully recreated if the resource object is still alive when <c>binary_to_term</c> is called. A <em>stale</em> resource term will be returned from <c>binary_to_term</c> if the resource object has @@ -2596,6 +2652,16 @@ enif_map_iterator_destroy(env, &iter);</code> </func> <func> + <name><ret>char*</ret> + <nametext>enif_mutex_name(ErlNifMutex* mtx)</nametext></name> + <fsummary></fsummary> + <desc> + <p>Same as <seealso marker="erl_driver#erl_drv_mutex_name"> + <c>erl_drv_mutex_name</c></seealso>.</p> + </desc> + </func> + + <func> <name><ret>int</ret> <nametext>enif_mutex_trylock(ErlNifMutex *mtx)</nametext></name> <fsummary></fsummary> @@ -2840,6 +2906,16 @@ enif_map_iterator_destroy(env, &iter);</code> </func> <func> + <name><ret>char*</ret> + <nametext>enif_rwlock_name(ErlNifRWLock* rwlck)</nametext></name> + <fsummary></fsummary> + <desc> + <p>Same as <seealso marker="erl_driver#erl_drv_rwlock_name"> + <c>erl_drv_rwlock_name</c></seealso>.</p> + </desc> + </func> + + <func> <name><ret>void</ret> <nametext>enif_rwlock_rlock(ErlNifRWLock *rwlck)</nametext></name> <fsummary></fsummary> @@ -2960,7 +3036,7 @@ enif_map_iterator_destroy(env, &iter);</code> <p>Argument <c>mode</c> describes the type of events to wait for. It can be <c>ERL_NIF_SELECT_READ</c>, <c>ERL_NIF_SELECT_WRITE</c> or a bitwise OR combination to wait for both. It can also be <c>ERL_NIF_SELECT_STOP</c> - which is described further below. When a read or write event is triggerred, + which is described further below. When a read or write event is triggered, a notification message like this is sent to the process identified by <c>pid</c>:</p> <code type="none">{select, Obj, Ref, ready_input | ready_output}</code> @@ -3011,7 +3087,7 @@ enif_map_iterator_destroy(env, &iter);</code> <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> + <p>Returns a negative value if the call failed where the following 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> @@ -3019,9 +3095,9 @@ enif_map_iterator_destroy(env, &iter);</code> <item>The system call failed to add the event object to the poll set.</item> </taglist> <note> - <p>Use bitwise AND to test for specific bits in the return vaue. + <p>Use bitwise AND to test for specific bits in 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 + information for both failed and successful calls. Do NOT use equality tests like <c>==</c>, as that may cause your application to stop working.</p> <p>Example:</p> <code type="none"> @@ -3044,9 +3120,10 @@ if (retval & ERL_NIF_SELECT_STOP_CALLED) { </name> <fsummary>Get the pid of the calling process.</fsummary> <desc> - <p>Initializes the pid variable <c>*pid</c> to represent the - calling process.</p> - <p>Returns <c>pid</c>.</p> + <p>Initializes the <seealso marker="#ErlNifPid"><c>ErlNifPid</c></seealso> + variable at <c>*pid</c> to represent the calling process.</p> + <p>Returns <c>pid</c> if successful, or NULL if <c>caller_env</c> is not + a <seealso marker="#ErlNifEnv">process-bound environment</seealso>.</p> </desc> </func> @@ -3085,7 +3162,7 @@ if (retval & ERL_NIF_SELECT_STOP_CALLED) { <c>enif_free_env</c></seealso> of cleared for reuse with <seealso marker="#enif_clear_env"><c>enif_clear_env</c></seealso>.</p> <p>If <c>msg_env</c> is set to <c>NULL</c>, the <c>msg</c> term is - copied and the original term and its environemt is still valid after + copied and the original term and its environment is still valid after the call.</p> <p>This function is only thread-safe when the emulator with SMP support is used. It can only be used in a non-SMP emulator from a NIF-calling @@ -3115,6 +3192,9 @@ if (retval & ERL_NIF_SELECT_STOP_CALLED) { <desc> <p>Similar to <c>snprintf</c> but this format string also accepts <c>"%T"</c>, which formats Erlang terms.</p> + <p>This function was originally intenden for debugging purpose. It is not + recommended to print very large terms with <c>%T</c>. The function may + change <c>errno</c>, even if successful.</p> </desc> </func> @@ -3178,6 +3258,16 @@ if (retval & ERL_NIF_SELECT_STOP_CALLED) { </func> <func> + <name><ret>char*</ret> + <nametext>enif_thread_name(ErlNifTid tid)</nametext></name> + <fsummary>Thread name</fsummary> + <desc> + <p>Same as <seealso marker="erl_driver#erl_drv_thread_name"> + <c>erl_drv_thread_name</c></seealso>.</p> + </desc> + </func> + + <func> <name><ret>ErlNifThreadOpts *</ret> <nametext>enif_thread_opts_create(char *name)</nametext></name> <fsummary></fsummary> @@ -3295,6 +3385,30 @@ if (retval & ERL_NIF_SELECT_STOP_CALLED) { <func> <name><ret>int</ret> + <nametext>enif_vfprintf(FILE *stream, const char *format, va_list ap) + </nametext></name> + <fsummary>Format strings and Erlang terms.</fsummary> + <desc> + <p>Equivalent to <seealso marker="#enif_fprintf"><c>enif_fprintf</c></seealso> + except that its called with a <c>va_list</c> instead of a variable number of + arguments.</p> + </desc> + </func> + + <func> + <name><ret>int</ret> + <nametext>enif_vsnprintf(char *str, size_t size, const char *format, va_list ap) + </nametext></name> + <fsummary>Format strings and Erlang terms.</fsummary> + <desc> + <p>Equivalent to <seealso marker="#enif_snprintf"><c>enif_snprintf</c></seealso> + except that its called with a <c>va_list</c> instead of a variable number of + arguments.</p> + </desc> + </func> + + <func> + <name><ret>int</ret> <nametext>enif_whereis_pid(ErlNifEnv *env, ERL_NIF_TERM name, ErlNifPid *pid)</nametext></name> <fsummary>Looks up a process by its registered name.</fsummary> |