text: // Copyright 2020 Open Source Robotics Foundation, Inc.
  //
  // 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.
  
  /// @file
  
  #ifndef RCL__RMW_IMPLEMENTATION_IDENTIFIER_CHECK_H_
  #define RCL__RMW_IMPLEMENTATION_IDENTIFIER_CHECK_H_
  
  #ifdef __cplusplus
  extern "C"
  {
  #endif
  
  #include "rcl/visibility_control.h"
  
  /// The environment variable name to control which RMW implementation is used.
  #define RMW_IMPLEMENTATION_ENV_VAR_NAME "RMW_IMPLEMENTATION"
  
  /// The environment variable name to control whether the chosen RMW implementation
  /// matches the one that is in use.
  #define RCL_ASSERT_RMW_ID_MATCHES_ENV_VAR_NAME "RCL_ASSERT_RMW_ID_MATCHES"
  
  /// Check whether the RMW implementation in use matches what the user requested.
  /**
   * \return #RCL_RET_OK if the RMW implementation in use matches what the user requested, or
   * \return #RCL_RET_MISMATCHED_RMW_ID if the RMW implementation does not match, or
   * \return #RCL_RET_BAD_ALLOC if memory allocation failed, or
   * \return #RCL_RET_ERROR if some other error occurred.
   */
  RCL_PUBLIC
  rcl_ret_t rcl_rmw_implementation_identifier_check(void);
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif  // RCL__RMW_IMPLEMENTATION_IDENTIFIER_CHECK_H_
  