diff options
Diffstat (limited to 'erts/doc/src/erl_nif.xml')
| -rw-r--r-- | erts/doc/src/erl_nif.xml | 230 |
1 files changed, 182 insertions, 48 deletions
diff --git a/erts/doc/src/erl_nif.xml b/erts/doc/src/erl_nif.xml index 4bad8b253c..f64381c99d 100644 --- a/erts/doc/src/erl_nif.xml +++ b/erts/doc/src/erl_nif.xml @@ -461,8 +461,9 @@ ok independent environment with all its terms is valid until you explicitly invalidates it with <seealso marker="#enif_free_env">enif_free_env</seealso> or <c>enif_send</c>.</p> - <p>All elements of a list/tuple must belong to the same environment as the - list/tuple itself. Terms can be copied between environments with + <p>All contained terms of a list/tuple/map must belong to the same + environment as the list/tuple/map itself. Terms can be copied between + environments with <seealso marker="#enif_make_copy">enif_make_copy</seealso>.</p> </item> <tag><marker id="ErlNifFunc"/>ErlNifFunc</tag> @@ -564,11 +565,11 @@ typedef enum { <funcs> <func><name><ret>void *</ret><nametext>enif_alloc(size_t size)</nametext></name> - <fsummary>Allocate dynamic memory.</fsummary> + <fsummary>Allocate dynamic memory</fsummary> <desc><p>Allocate memory of <c>size</c> bytes. Return NULL if allocation failed.</p></desc> </func> <func><name><ret>int</ret><nametext>enif_alloc_binary(size_t size, ErlNifBinary* bin)</nametext></name> - <fsummary>Create a new binary.</fsummary> + <fsummary>Create a new binary</fsummary> <desc><p>Allocate a new binary of size <c>size</c> bytes. Initialize the structure pointed to by <c>bin</c> to refer to the allocated binary. The binary must either be released by @@ -595,7 +596,7 @@ typedef enum { <desc><p>Allocate a memory managed resource object of type <c>type</c> and size <c>size</c> bytes.</p></desc> </func> <func><name><ret>void</ret><nametext>enif_clear_env(ErlNifEnv* env)</nametext></name> - <fsummary>Clear an environment for reuse.</fsummary> + <fsummary>Clear an environment for reuse</fsummary> <desc><p>Free all terms in an environment and clear it for reuse. The environment must have been allocated with <seealso marker="#enif_alloc_env">enif_alloc_env</seealso>. </p></desc> @@ -683,14 +684,14 @@ typedef enum { <c>size-1</c>.</p></desc> </func> <func><name><ret>int</ret><nametext>enif_get_atom_length(ErlNifEnv* env, ERL_NIF_TERM term, unsigned* len, ErlNifCharEncoding encode)</nametext></name> - <fsummary>Get the length of atom <c>term</c>.</fsummary> + <fsummary>Get the length of atom <c>term</c></fsummary> <desc><p>Set <c>*len</c> to the length (number of bytes excluding terminating null character) of the atom <c>term</c> with encoding <c>encode</c>. Return true on success or false if <c>term</c> is not an atom.</p></desc> </func> <func><name><ret>int</ret><nametext>enif_get_double(ErlNifEnv* env, ERL_NIF_TERM term, double* dp)</nametext></name> - <fsummary>Read a floating-point number term.</fsummary> + <fsummary>Read a floating-point number term</fsummary> <desc><p>Set <c>*dp</c> to the floating point value of <c>term</c>. Return true on success or false if <c>term</c> is not a float.</p></desc> </func> @@ -719,17 +720,28 @@ typedef enum { non-empty list.</p></desc> </func> <func><name><ret>int</ret><nametext>enif_get_list_length(ErlNifEnv* env, ERL_NIF_TERM term, unsigned* len)</nametext></name> - <fsummary>Get the length of list <c>term</c>.</fsummary> + <fsummary>Get the length of list <c>term</c></fsummary> <desc><p>Set <c>*len</c> to the length of list <c>term</c> and return true, or return false if <c>term</c> is not a list.</p></desc> </func> <func><name><ret>int</ret><nametext>enif_get_long(ErlNifEnv* env, ERL_NIF_TERM term, long int* ip)</nametext></name> - <fsummary>Read an long integer term.</fsummary> + <fsummary>Read an long integer term</fsummary> <desc><p>Set <c>*ip</c> to the long integer value of <c>term</c> and return true, or return false if <c>term</c> is not an integer or is outside the bounds of type <c>long int</c>.</p></desc> </func> - <func><name><ret>int</ret><nametext>enif_get_resource(ErlNifEnv* env, ERL_NIF_TERM term, ErlNifResourceType* type, void** objp)</nametext></name> + <func><name><ret>int</ret><nametext>enif_get_map_size(ErlNifEnv* env, ERL_NIF_TERM term, size_t *size)</nametext></name> + <fsummary>Read the size of a map term</fsummary> + <desc><p>Set <c>*size</c> to the number of key-value pairs in the map <c>term</c> and + return true, or return false if <c>term</c> is not a map.</p></desc> + </func> + <func><name><ret>int</ret><nametext>enif_get_map_value(ErlNifEnv* env, ERL_NIF_TERM map, ERL_NIF_TERM key, ERL_NIF_TERM* value)</nametext></name> + <fsummary>Get the value of a key in a map</fsummary> + <desc><p>Set <c>*value</c> to the value associated with <c>key</c> in the + map <c>map</c> and return true. Return false if <c>map</c> is not a map + or if <c>map</c> does not contain <c>key</c>.</p></desc> + </func> + <func><name><ret>int</ret><nametext>enif_get_resource(ErlNifEnv* env, ERL_NIF_TERM term, ErlNifResourceType* type, void** objp)</nametext></name> <fsummary>Get the pointer to a resource object</fsummary> <desc><p>Set <c>*objp</c> to point to the resource object referred to by <c>term</c>.</p> <p>Return true on success or false if <c>term</c> is not a handle to a resource object @@ -738,7 +750,7 @@ typedef enum { <func><name><ret>int</ret><nametext>enif_get_string(ErlNifEnv* env, ERL_NIF_TERM list, char* buf, unsigned size, ErlNifCharEncoding encode)</nametext></name> - <fsummary>Get a C-string from a list.</fsummary> + <fsummary>Get a C-string from a list</fsummary> <desc><p>Write a null-terminated string, in the buffer pointed to by <c>buf</c> with size <c>size</c>, consisting of the characters in the string <c>list</c>. The characters are written using encoding @@ -751,7 +763,7 @@ typedef enum { <c>size</c> is less than 1.</p></desc> </func> <func><name><ret>int</ret><nametext>enif_get_tuple(ErlNifEnv* env, ERL_NIF_TERM term, int* arity, const ERL_NIF_TERM** array)</nametext></name> - <fsummary>Inspect the elements of a tuple.</fsummary> + <fsummary>Inspect the elements of a tuple</fsummary> <desc><p>If <c>term</c> is a tuple, set <c>*array</c> to point to an array containing the elements of the tuple and set <c>*arity</c> to the number of elements. Note that the array @@ -761,28 +773,35 @@ typedef enum { tuple.</p></desc> </func> <func><name><ret>int</ret><nametext>enif_get_uint(ErlNifEnv* env, ERL_NIF_TERM term, unsigned int* ip)</nametext></name> - <fsummary>Read an unsigned integer term.</fsummary> + <fsummary>Read an unsigned integer term</fsummary> <desc><p>Set <c>*ip</c> to the unsigned integer value of <c>term</c> and return true, or return false if <c>term</c> is not an unsigned integer or is outside the bounds of type <c>unsigned int</c>.</p></desc> </func> <func><name><ret>int</ret><nametext>enif_get_uint64(ErlNifEnv* env, ERL_NIF_TERM term, ErlNifUInt64* ip)</nametext></name> - <fsummary>Read an unsigned 64-bit integer term.</fsummary> + <fsummary>Read an unsigned 64-bit integer term</fsummary> <desc><p>Set <c>*ip</c> to the unsigned integer value of <c>term</c> and return true, or return false if <c>term</c> is not an unsigned integer or is outside the bounds of an unsigned 64-bit integer.</p></desc> </func> <func><name><ret>int</ret><nametext>enif_get_ulong(ErlNifEnv* env, ERL_NIF_TERM term, unsigned long* ip)</nametext></name> - <fsummary>Read an unsigned integer term.</fsummary> + <fsummary>Read an unsigned integer term</fsummary> <desc><p>Set <c>*ip</c> to the unsigned long integer value of <c>term</c> and return true, or return false if <c>term</c> is not an unsigned integer or is outside the bounds of type <c>unsigned long</c>.</p></desc> </func> - <func><name><ret>int</ret><nametext>enif_has_pending_exception(ErlNifEnv* env)</nametext></name> - <fsummary>Check if an exception has been raised.</fsummary> + <func><name><ret>int</ret><nametext>enif_has_pending_exception(ErlNifEnv* env, ERL_NIF_TERM* reason)</nametext></name> + <fsummary>Check if an exception has been raised</fsummary> <desc><p>Return true if a pending exception is associated - with the environment <c>env</c>. The only possible exception is currently - <c>badarg</c> (see <seealso marker="#enif_make_badarg">enif_make_badarg</seealso>).</p></desc> + with the environment <c>env</c>. If <c>reason</c> is a null pointer, ignore it. + Otherwise, if there's a pending exception associated with <c>env</c>, set the ERL_NIF_TERM + to which <c>reason</c> points to the value of the exception's term. For example, if + <seealso marker="#enif_make_badarg">enif_make_badarg</seealso> is called to set a + pending <c>badarg</c> exception, a subsequent call to <c>enif_has_pending_exception(env, &reason)</c> + will set <c>reason</c> to the atom <c>badarg</c>, then return true.</p> + <p>See also: <seealso marker="#enif_make_badarg">enif_make_badarg</seealso> + and <seealso marker="#enif_raise_exception">enif_raise_exception</seealso>.</p> + </desc> </func> <func><name><ret>int</ret><nametext>enif_inspect_binary(ErlNifEnv* env, ERL_NIF_TERM bin_term, ErlNifBinary* bin)</nametext></name> <fsummary>Inspect the content of a binary</fsummary> @@ -817,6 +836,10 @@ typedef enum { <fsummary>Determine if a term is an exception</fsummary> <desc><p>Return true if <c>term</c> is an exception.</p></desc> </func> + <func><name><ret>int</ret><nametext>enif_is_map(ErlNifEnv* env, ERL_NIF_TERM term)</nametext></name> + <fsummary>Determine if a term is a map</fsummary> + <desc><p>Return true if <c>term</c> is a map, false otherwise.</p></desc> + </func> <func><name><ret>int</ret><nametext>enif_is_number(ErlNifEnv* env, ERL_NIF_TERM term)</nametext></name> <fsummary>Determine if a term is a number (integer or float)</fsummary> <desc><p>Return true if <c>term</c> is a number.</p></desc> @@ -890,18 +913,19 @@ typedef enum { </p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_badarg(ErlNifEnv* env)</nametext></name> - <fsummary>Make a badarg exception.</fsummary> + <fsummary>Make a badarg exception</fsummary> <desc><p>Make a badarg exception to be returned from a NIF, and associate it with the environment <c>env</c>. Once a NIF or any function it calls invokes <c>enif_make_badarg</c>, the runtime ensures that a <c>badarg</c> exception is raised when the NIF returns, even if the NIF attempts to return a non-exception term instead. - The return value from <c>enif_make_badarg</c> may only be used as - return value from the NIF that invoked it (direct or indirectly) + The return value from <c>enif_make_badarg</c> may be used only as the + return value from the NIF that invoked it (directly or indirectly) or be passed to <seealso marker="#enif_is_exception">enif_is_exception</seealso>, but not to any other NIF API function.</p> - <p>See also: <seealso marker="#enif_has_pending_exception">enif_has_pending_exception</seealso>. + <p>See also: <seealso marker="#enif_has_pending_exception">enif_has_pending_exception</seealso> + and <seealso marker="#enif_raise_exception">enif_raise_exception</seealso> </p> <note><p>In earlier versions (older than erts-7.0, OTP 18) the return value from <c>enif_make_badarg</c> had to be returned from the NIF. This @@ -909,14 +933,14 @@ typedef enum { if <c>enif_make_badarg</c> has been invoked.</p></note></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_binary(ErlNifEnv* env, ErlNifBinary* bin)</nametext></name> - <fsummary>Make a binary term.</fsummary> + <fsummary>Make a binary term</fsummary> <desc><p>Make a binary term from <c>bin</c>. Any ownership of the binary data will be transferred to the created term and <c>bin</c> should be considered read-only for the rest of the NIF call and then as released.</p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_copy(ErlNifEnv* dst_env, ERL_NIF_TERM src_term)</nametext></name> - <fsummary>Make a copy of a term.</fsummary> + <fsummary>Make a copy of a term</fsummary> <desc><p>Make a copy of term <c>src_term</c>. The copy will be created in environment <c>dst_env</c>. The source term may be located in any environment.</p></desc> @@ -957,7 +981,7 @@ typedef enum { <desc><p>Create an integer term from a signed 64-bit integer.</p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_list(ErlNifEnv* env, unsigned cnt, ...)</nametext></name> - <fsummary>Create a list term.</fsummary> + <fsummary>Create a list term</fsummary> <desc><p>Create an ordinary list term of length <c>cnt</c>. Expects <c>cnt</c> number of arguments (after <c>cnt</c>) of type ERL_NIF_TERM as the elements of the list. An empty list is returned if <c>cnt</c> is 0.</p></desc> @@ -971,28 +995,21 @@ typedef enum { <name><ret>ERL_NIF_TERM</ret><nametext>enif_make_list7(ErlNifEnv* env, ERL_NIF_TERM e1, ..., ERL_NIF_TERM e7)</nametext></name> <name><ret>ERL_NIF_TERM</ret><nametext>enif_make_list8(ErlNifEnv* env, ERL_NIF_TERM e1, ..., ERL_NIF_TERM e8)</nametext></name> <name><ret>ERL_NIF_TERM</ret><nametext>enif_make_list9(ErlNifEnv* env, ERL_NIF_TERM e1, ..., ERL_NIF_TERM e9)</nametext></name> - <fsummary>Create a list term.</fsummary> + <fsummary>Create a list term</fsummary> <desc><p>Create an ordinary list term with length indicated by the function name. Prefer these functions (macros) over the variadic <c>enif_make_list</c> to get a compile time error if the number of arguments does not match.</p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_list_cell(ErlNifEnv* env, ERL_NIF_TERM head, ERL_NIF_TERM tail)</nametext></name> - <fsummary>Create a list cell.</fsummary> + <fsummary>Create a list cell</fsummary> <desc><p>Create a list cell <c>[head | tail]</c>.</p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_list_from_array(ErlNifEnv* env, const ERL_NIF_TERM arr[], unsigned cnt)</nametext></name> - <fsummary>Create a list term from an array.</fsummary> + <fsummary>Create a list term from an array</fsummary> <desc><p>Create an ordinary list containing the elements of array <c>arr</c> of length <c>cnt</c>. An empty list is returned if <c>cnt</c> is 0.</p></desc> </func> - <func><name><ret>int</ret><nametext>enif_make_reverse_list(ErlNifEnv* env, ERL_NIF_TERM term, ERL_NIF_TERM *list)</nametext></name> - <fsummary>Create the reverse list of the list <c>term</c>.</fsummary> - <desc><p>Set <c>*list</c> to the reverse list of the list <c>term</c> and return true, - or return false if <c>term</c> is not a list. This function should only be used on - short lists as a copy will be created of the list which will not be released until after the - nif returns.</p></desc> - </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_long(ErlNifEnv* env, long int i)</nametext></name> <fsummary>Create an integer term from a long int</fsummary> <desc><p>Create an integer term from a <c>long int</c>.</p></desc> @@ -1007,12 +1024,42 @@ typedef enum { reallocated.</p><p>Return a pointer to the raw binary data and set <c>*termp</c> to the binary term.</p></desc> </func> + <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_new_map(ErlNifEnv* env)</nametext></name> + <fsummary>Make an empty map term</fsummary> + <desc><p>Make an empty map term.</p></desc> + </func> + <func><name><ret>int</ret><nametext>enif_make_map_put(ErlNifEnv* env, ERL_NIF_TERM map_in, ERL_NIF_TERM key, ERL_NIF_TERM value, ERL_NIF_TERM* map_out)</nametext></name> + <fsummary>Insert key-value pair in map</fsummary> + <desc><p>Make a copy of map <c>map_in</c> and insert <c>key</c> with + <c>value</c>. If <c>key</c> already exists in <c>map_in</c>, the old + associated value is replaced by <c>value</c>. If successful set + <c>*map_out</c> to the new map and return true. Return false if + <c>map_in</c> is not a map.</p> + <p>The <c>map_in</c> term must belong to the environment <c>env</c>.</p></desc> + </func> + <func><name><ret>int</ret><nametext>enif_make_map_update(ErlNifEnv* env, ERL_NIF_TERM map_in, ERL_NIF_TERM key, ERL_NIF_TERM new_value, ERL_NIF_TERM* map_out)</nametext></name> + <fsummary>Replace value for key in map</fsummary> + <desc><p>Make a copy of map <c>map_in</c> and replace the old associated + value for <c>key</c> with <c>new_value</c>. If successful set + <c>*map_out</c> to the new map and return true. Return false if + <c>map_in</c> is not a map or if it does no contain <c>key</c>.</p> + <p>The <c>map_in</c> term must belong to the environment <c>env</c>.</p></desc> + </func> + <func><name><ret>int</ret><nametext>enif_make_map_remove(ErlNifEnv* env, ERL_NIF_TERM map_in, ERL_NIF_TERM key, ERL_NIF_TERM* map_out)</nametext></name> + <fsummary>Remove key from map</fsummary> + <desc><p>If map <c>map_in</c> contains <c>key</c>, make a copy of + <c>map_in</c> in <c>*map_out</c> and remove <c>key</c> and associated + value. If map <c>map_in</c> does not contain <c>key</c>, set + <c>*map_out</c> to <c>map_in</c>. Return true for success or false if + <c>map_in</c> is not a map.</p> + <p>The <c>map_in</c> term must belong to the environment <c>env</c>.</p></desc> + </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_pid(ErlNifEnv* env, const ErlNifPid* pid)</nametext></name> <fsummary>Make a pid term</fsummary> <desc><p>Make a pid term from <c>*pid</c>.</p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_ref(ErlNifEnv* env)</nametext></name> - <fsummary>Create a reference.</fsummary> + <fsummary>Create a reference</fsummary> <desc><p>Create a reference like <seealso marker="erlang#make_ref-0">erlang:make_ref/0</seealso>.</p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_resource(ErlNifEnv* env, void* obj)</nametext></name> @@ -1050,20 +1097,28 @@ typedef enum { <seealso marker="#enif_release_resource">enif_release_resource</seealso>.</p> </desc> </func> + <func><name><ret>int</ret><nametext>enif_make_reverse_list(ErlNifEnv* env, ERL_NIF_TERM list_in, ERL_NIF_TERM *list_out)</nametext></name> + <fsummary>Create the reverse of a list</fsummary> + <desc><p>Set <c>*list_out</c> to the reverse list of the list <c>list_in</c> and return true, + or return false if <c>list_in</c> is not a list. This function should only be used on + short lists as a copy will be created of the list which will not be released until after the + nif returns.</p> + <p>The <c>list_in</c> term must belong to the environment <c>env</c>.</p></desc> + </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_string(ErlNifEnv* env, const char* string, ErlNifCharEncoding encoding)</nametext></name> - <fsummary>Create a string.</fsummary> + <fsummary>Create a string</fsummary> <desc><p>Create a list containing the characters of the null-terminated string <c>string</c> with encoding <seealso marker="#ErlNifCharEncoding">encoding</seealso>.</p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_string_len(ErlNifEnv* env, const char* string, size_t len, ErlNifCharEncoding encoding)</nametext></name> - <fsummary>Create a string.</fsummary> + <fsummary>Create a string</fsummary> <desc><p>Create a list containing the characters of the string <c>string</c> with length <c>len</c> and encoding <seealso marker="#ErlNifCharEncoding">encoding</seealso>. Null-characters are treated as any other characters.</p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_sub_binary(ErlNifEnv* env, ERL_NIF_TERM bin_term, size_t pos, size_t size)</nametext></name> - <fsummary>Make a subbinary term.</fsummary> + <fsummary>Make a subbinary term</fsummary> <desc><p>Make a subbinary of binary <c>bin_term</c>, starting at zero-based position <c>pos</c> with a length of <c>size</c> bytes. <c>bin_term</c> must be a binary or bitstring and @@ -1071,7 +1126,7 @@ typedef enum { bytes in <c>bin_term</c>.</p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_tuple(ErlNifEnv* env, unsigned cnt, ...)</nametext></name> - <fsummary>Create a tuple term.</fsummary> + <fsummary>Create a tuple term</fsummary> <desc><p>Create a tuple term of arity <c>cnt</c>. Expects <c>cnt</c> number of arguments (after <c>cnt</c>) of type ERL_NIF_TERM as the elements of the tuple.</p></desc> @@ -1085,14 +1140,14 @@ typedef enum { <name><ret>ERL_NIF_TERM</ret><nametext>enif_make_tuple7(ErlNifEnv* env, ERL_NIF_TERM e1, ..., ERL_NIF_TERM e7)</nametext></name> <name><ret>ERL_NIF_TERM</ret><nametext>enif_make_tuple8(ErlNifEnv* env, ERL_NIF_TERM e1, ..., ERL_NIF_TERM e8)</nametext></name> <name><ret>ERL_NIF_TERM</ret><nametext>enif_make_tuple9(ErlNifEnv* env, ERL_NIF_TERM e1, ..., ERL_NIF_TERM e9)</nametext></name> - <fsummary>Create a tuple term.</fsummary> + <fsummary>Create a tuple term</fsummary> <desc><p>Create a tuple term with length indicated by the function name. Prefer these functions (macros) over the variadic <c>enif_make_tuple</c> to get a compile time error if the number of arguments does not match.</p></desc> </func> <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_make_tuple_from_array(ErlNifEnv* env, const ERL_NIF_TERM arr[], unsigned cnt)</nametext></name> - <fsummary>Create a tuple term from an array.</fsummary> + <fsummary>Create a tuple term from an array</fsummary> <desc><p>Create a tuple containing the elements of array <c>arr</c> of length <c>cnt</c>.</p></desc> </func> @@ -1108,6 +1163,72 @@ typedef enum { <fsummary>Create an integer term from an unsigned long int</fsummary> <desc><p>Create an integer term from an <c>unsigned long int</c>.</p></desc> </func> + <func><name><ret>int</ret><nametext>enif_map_iterator_create(ErlNifEnv *env, ERL_NIF_TERM map, ErlNifMapIterator *iter, ErlNifMapIteratorEntry entry)</nametext></name> + <fsummary>Create a map iterator</fsummary> + <desc><p>Create an iterator for the map <c>map</c> by initializing the + structure pointed to by <c>iter</c>. The <c>entry</c> argument determines + the start position of the iterator: <c>ERL_NIF_MAP_ITERATOR_FIRST</c> or + <c>ERL_NIF_MAP_ITERATOR_LAST</c>. Return true on success or false if + <c>map</c> is not a map.</p> + <p>A map iterator is only useful during the lifetime of the environment + <c>env</c> that the <c>map</c> belongs to. The iterator must be destroyed by + calling <seealso marker="#enif_map_iterator_destroy"> + enif_map_iterator_destroy</seealso>.</p> + <code type="none"> +ERL_NIF_TERM key, value; +ErlNifMapIterator iter; +enif_map_iterator_create(env, my_map, ERL_NIF_MAP_ITERATOR_FIRST); + +while (enif_map_iterator_get_pair(env, &iter, &key, &value)) { + do_something(key,value); + enif_map_iterator_next(env, &iter); +} +enif_map_iterator_destroy(env, &iter); + </code> + <note><p>The key-value pairs of a map have no defined iteration + order. The only guarantee is that the iteration order of a single map + instance is preserved during the lifetime of the environment that the map + belongs to.</p> + </note> + </desc> + </func> + <func><name><ret>void</ret><nametext>enif_map_iterator_destroy(ErlNifEnv *env, ErlNifMapIterator *iter)</nametext></name> + <fsummary>Destroy a map iterator</fsummary> + <desc><p>Destroy a map iterator created by + <seealso marker="#enif_map_iterator_create">enif_map_iterator_create</seealso>. + </p></desc> + </func> + <func><name><ret>int</ret><nametext>enif_map_iterator_get_pair(ErlNifEnv *env, ErlNifMapIterator *iter, ERL_NIF_TERM *key, ERL_NIF_TERM *value)</nametext></name> + <fsummary>Get key and value at current map iterator position</fsummary> + <desc><p>Get key and value terms at current map iterator position. + On success set <c>*key</c> and <c>*value</c> and return true. + Return false if the iterator is positioned at head (before first entry) + or tail (beyond last entry).</p></desc> + </func> + <func><name><ret>int</ret><nametext>enif_map_iterator_is_head(ErlNifEnv *env, ErlNifMapIterator *iter)</nametext></name> + <fsummary>Check if map iterator is positioned before first</fsummary> + <desc><p>Return true if map iterator <c>iter</c> is positioned + before first entry.</p></desc> + </func> + <func><name><ret>int</ret><nametext>enif_map_iterator_is_tail(ErlNifEnv *env, ErlNifMapIterator *iter)</nametext></name> + <fsummary>Check if map iterator is positioned after last</fsummary> + <desc><p>Return true if map iterator <c>iter</c> is positioned + after last entry.</p></desc> + </func> + <func><name><ret>int</ret><nametext>enif_map_iterator_next(ErlNifEnv *env, ErlNifMapIterator *iter)</nametext></name> + <fsummary>Increment map iterator to point to next entry</fsummary> + <desc><p>Increment map iterator to point to next key-value entry. + Return true if the iterator is now positioned at a valid key-value entry, + or false if the iterator is positioned at the tail (beyond the last + entry).</p></desc> + </func> + <func><name><ret>int</ret><nametext>enif_map_iterator_prev(ErlNifEnv *env, ErlNifMapIterator *iter)</nametext></name> + <fsummary>Decrement map iterator to point to previous entry</fsummary> + <desc><p>Decrement map iterator to point to previous key-value entry. + Return true if the iterator is now positioned at a valid key-value entry, + or false if the iterator is positioned at the head (before the first + entry).</p></desc> + </func> <func><name><ret>ErlNifMutex *</ret><nametext>enif_mutex_create(char *name)</nametext></name> <fsummary></fsummary> <desc><p>Same as <seealso marker="erl_driver#erl_drv_mutex_create">erl_drv_mutex_create</seealso>. @@ -1168,19 +1289,32 @@ typedef enum { <c>reload</c> or <c>upgrade</c>.</p> <p>Was previously named <c>enif_get_data</c>.</p></desc> </func> + <func><name><ret>ERL_NIF_TERM</ret><nametext>enif_raise_exception(ErlNifEnv* env, ERL_NIF_TERM reason)</nametext></name> + <fsummary>Raise a NIF error exception</fsummary> + <desc><p>Create an error exception with the term <c>reason</c> to be returned from a NIF, + and associate it with the environment <c>env</c>. Once a NIF or any function it calls + invokes <c>enif_raise_exception</c>, the runtime ensures that the exception it creates + is raised when the NIF returns, even if the NIF attempts to return a non-exception + term instead. The return value from <c>enif_raise_exception</c> may be used only as + the return value from the NIF that invoked it (directly or indirectly) or be passed + to <seealso marker="#enif_is_exception">enif_is_exception</seealso>, but + not to any other NIF API function.</p> + <p>See also: <seealso marker="#enif_has_pending_exception">enif_has_pending_exception</seealso> + and <seealso marker="#enif_make_badarg">enif_make_badarg</seealso>.</p></desc> + </func> <func><name><ret>int</ret><nametext>enif_realloc_binary(ErlNifBinary* bin, size_t size)</nametext></name> - <fsummary>Change the size of a binary.</fsummary> + <fsummary>Change the size of a binary</fsummary> <desc><p>Change the size of a binary <c>bin</c>. The source binary may be read-only, in which case it will be left untouched and a mutable copy is allocated and assigned to <c>*bin</c>. Return true on success, false if memory allocation failed.</p></desc> </func> <func><name><ret>void</ret><nametext>enif_release_binary(ErlNifBinary* bin)</nametext></name> - <fsummary>Release a binary.</fsummary> + <fsummary>Release a binary</fsummary> <desc><p>Release a binary obtained from <c>enif_alloc_binary</c>.</p></desc> </func> <func><name><ret>void</ret><nametext>enif_release_resource(void* obj)</nametext></name> - <fsummary>Release a resource object.</fsummary> + <fsummary>Release a resource object</fsummary> <desc><p>Remove a reference to resource object <c>obj</c>obtained from <seealso marker="#enif_alloc_resource">enif_alloc_resource</seealso>. The resource object will be destructed when the last reference is removed. @@ -1256,12 +1390,12 @@ typedef enum { </desc> </func> <func><name><ret>ErlNifPid *</ret><nametext>enif_self(ErlNifEnv* caller_env, ErlNifPid* pid)</nametext></name> - <fsummary>Get the pid of the calling process.</fsummary> + <fsummary>Get the pid of the calling process</fsummary> <desc><p>Initialize the pid variable <c>*pid</c> to represent the calling process. Return <c>pid</c>.</p></desc> </func> <func><name><ret>int</ret><nametext>enif_send(ErlNifEnv* env, ErlNifPid* to_pid, ErlNifEnv* msg_env, ERL_NIF_TERM msg)</nametext></name> - <fsummary>Send a message to a process.</fsummary> + <fsummary>Send a message to a process</fsummary> <desc><p>Send a message to a process.</p> <taglist> <tag><c>env</c></tag> |