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@stdlib/napi

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C APIs for creating Node-API native add-ons.

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<!-- @license Apache-2.0 Copyright (c) 2024 The Stdlib Authors. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> # create_uint32 > Convert an unsigned 32-bit integer to a Node-API value. <!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. --> <section class="intro"> </section> <!-- /.intro --> <!-- Package usage documentation. --> <section class="usage"> ## Usage ```javascript var headerDir = require( '@stdlib/napi/create-uint32' ); ``` #### headerDir Absolute file path for the directory containing header files for C APIs. ```javascript var dir = headerDir; // returns <string> ``` </section> <!-- /.usage --> <!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. --> <section class="notes"> </section> <!-- /.notes --> <!-- Package usage examples. --> <section class="examples"> ## Examples ```javascript var headerDir = require( '@stdlib/napi/create-uint32' ); console.log( headerDir ); // => <string> ``` </section> <!-- /.examples --> <!-- C interface documentation. --> * * * <section class="c"> ## C APIs <!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. --> <section class="intro"> </section> <!-- /.intro --> <!-- C usage documentation. --> <section class="usage"> ### Usage ```c #include "stdlib/napi/create_uint32.h" ``` #### stdlib_napi_create_uint32( env, value, \*out ) Converts an unsigned 32-bit integer to a Node-API value. ```c #include "stdlib/napi/create_uint32.h" #include <node_api.h> static napi_value addon( napi_env env, napi_callback_info info ) { // ... napi_value value; napi_status status = stdlib_napi_create_uint32( env, 1, &value ); assert( status == napi_ok ); if ( err != NULL ) { assert( napi_throw( env, err ) == napi_ok ); return NULL; } // ... } ``` The function accepts the following arguments: - **env**: `[in] napi_env` environment under which the function is invoked. - **value**: `[in] uint32_t` unsigned 32-bit integer. - **out**: `[out] napi_value*` destination for storing output value. ```c napi_status stdlib_napi_create_uint32( const napi_env env, const uint32_t value, napi_value *out ); ``` The function returns a `napi_status` status code indicating success or failure (returns `napi_ok` if success). #### STDLIB_NAPI_CREATE_UINT32( env, expression, name ) Macro for converting an unsigned 32-bit integer to a Node-API value. ```c #include "stdlib/napi/create_uint32.h" #include "stdlib/napi/argv_uint32.h" #include "stdlib/napi/argv.h" #include <node_api.h> #include <stdint.h> static uint32_t fcn( const uint32_t v ) { return v; } // ... static napi_value addon( napi_env env, napi_callback_info info ) { // Retrieve add-on callback arguments: STDLIB_NAPI_ARGV( env, info, argv, argc, 1 ); // Convert the first argument to a C type: STDLIB_NAPI_ARGV_UINT32( env, value, argv, 0 ); // ... // Convert a value having a C type to a Node-API value: STDLIB_NAPI_CREATE_UINT32( env, fcn( value ), out ); return out; } ``` The macro expects the following arguments: - **env**: environment under which the callback is invoked. - **expression**: expression returning an unsigned 32-bit integer. - **name**: output variable name. </section> <!-- /.usage --> <!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. --> <section class="notes"> </section> <!-- /.notes --> <!-- C API usage examples. --> <section class="examples"> </section> <!-- /.examples --> </section> <!-- /.c --> <!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. --> <section class="references"> </section> <!-- /.references --> <!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. --> <section class="related"> </section> <!-- /.related --> <!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. --> <section class="links"> </section> <!-- /.links -->