env.hpp

// Copyright (c) 2007 The NetBSD Foundation, Inc.
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#if !defined(ATF_CXX_DETAIL_ENV_HPP)
#define ATF_CXX_DETAIL_ENV_HPP

#include <string>

namespace atf {
namespace env {

// ------------------------------------------------------------------------
// Free functions.
// ------------------------------------------------------------------------

//!
//! \brief Returns the value of an environment variable.
//!
//! Returns the value of the specified environment variable.  The variable
//! must be defined.
//!
std::string get(const std::string&);

//!
//! \brief Returns the value of an environment variable with a default.
//!
std::string get(const std::string&, const std::string&);

//!
//! \brief Checks if the environment has a variable.
//!
//! Checks if the environment has a given variable.
//!
bool has(const std::string&);

//!
//! \brief Sets an environment variable to a given value.
//!
//! Sets the specified environment variable to the given value.  Note that
//! variables set to the empty string are different to undefined ones.
//!
//! Be aware that this alters the program's global status, which in general
//! is a bad thing to do due to the side-effects it may have.  There are
//! some legitimate usages for this function, though.
//!
void set(const std::string&, const std::string&);

//!
//! \brief Unsets an environment variable.
//!
//! Unsets the specified environment variable  Note that undefined
//! variables are different to those defined but set to an empty value.
//!
//! Be aware that this alters the program's global status, which in general
//! is a bad thing to do due to the side-effects it may have.  There are
//! some legitimate usages for this function, though.
//!
void unset(const std::string&);

} // namespace env
} // namespace atf

#endif // !defined(ATF_CXX_DETAIL_ENV_HPP)