get_env.hpp

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#ifndef RCPPUTILS__GET_ENV_HPP_
#define RCPPUTILS__GET_ENV_HPP_
 
#include "rcutils/get_env.h"
 
#include <stdexcept>
#include <string>
 
#include "rcpputils/visibility_control.hpp"
 
namespace rcpputils
{
 
/*
 * \param[in] env_var the name of the environment variable
 * \return The value of the environment variable if it exists, or "".
 * \throws std::runtime_error on error
 */
std::string get_env_var(const char * env_var)
{
  const char * value{};
  const char * err = rcutils_get_env(env_var, &value);
  if (err) {
    throw std::runtime_error(err);
  }
  return value ? value : "";
}
 
}  // namespace rcpputils
 
#endif  // RCPPUTILS__GET_ENV_HPP_