From 7f303cc4b68e2cc64444130eb082ee675c16e5f2 Mon Sep 17 00:00:00 2001 From: Peter Dimov Date: Wed, 3 Oct 2018 01:19:28 +0300 Subject: [PATCH] Remove old .html files; update redirect --- doc/index.html | 163 --------- doc/reference.html | 834 --------------------------------------------- index.html | 17 +- 3 files changed, 9 insertions(+), 1005 deletions(-) delete mode 100644 doc/index.html delete mode 100644 doc/reference.html diff --git a/doc/index.html b/doc/index.html deleted file mode 100644 index e89df5a..0000000 --- a/doc/index.html +++ /dev/null @@ -1,163 +0,0 @@ - - - - - - - -Boost System Library - - - - - - - - - - -
- -boost.png (6897 bytes) - System Library -
- - - - - -
Boost Home    - Library Home   Tutorial   - Reference
- - - - - - - - - - - - - - -
- Contents
- Introduction
- Release History
- Design Rationale
- History
- Acknowledgements -
- Headers
- <boost/system/error_code.hpp>
- - <boost/system/system_error.hpp>
- - <boost/system/cygwin_error.hpp>
- - <boost/system/linux_error.hpp>
- - <boost/system/windows_error.hpp>
- -

Introduction

- -

Error conditions originating from the operating system or other low-level -application program interfaces (API's) are typically reported via an integer -representing an error code. When these low-level API calls are wrapped in -portable code, such as in a portable library, some users want to deal with the -error codes in portable ways. Other users need to get at the system specific -error codes, so they can deal with system specific needs. The Boost System -library provides simple, light-weight -error_code objects that encapsulate system-specific error code values, yet -also provide access to more abstract and portable error conditions via -error_condition objects. -Because error_code objects can represent errors from sources other than the -operating system, including user-defined sources, each error_code and -error_condition has an associated -error_category.

- -

An exception class,  -system_error, is provided. Derived from std::runtime_error, it captures the -underlying error_code for the problem causing the exception so that this -important information is not lost.

-

While exceptions are the preferred C++ default error code reporting -mechanism, users of libraries dependent on low-level API's often need overloads -reporting error conditions via error code arguments and/or return values rather -than via throwing exceptions. Otherwise, when errors are not exceptional -occurrences and must be dealt with as they arise, programs become littered with -try/catch blocks, unreadable, and very inefficient. The Boost System library -supports both error reporting by exception and by error code.

-

In addition to portable errors codes and conditions supported by the -error_code.hpp header, system-specific headers support the Cygwin, Linux, -and Windows platforms. These headers are effectively no-ops if included for -platforms other than their intended target.

- - - - -
The Boost System Library is part of the C++11 Standard Library. - A number of changes, particularly to names, were made by the C++ committee - during standardization. The Boost implementation is tracking those changes. - See Deprecated names for - synonyms provided to prevent breakage of existing user code. See - Breaking changes for changes - that unavoidably break existing user code. All breaking changes are noisy - and will cause compile-time errors.
-

Release History

-

system-2014-06-02: First modular Boost release. Minor -maintenance changes.

-

Design Rationale

-

Class error_code  and error_condition are designed as a value types so -they can be copied -without slicing and do not requiring heap allocation, but still have polymorphic -behavior based on the error category. This is achieved by abstract base class -error_category supplying the polymorphic behavior, and -error_code and error_condition containing a pointer to an object of a type derived from -error_category.

-

Many of the detailed design decisions were driven by the requirements that -users to be able to add additional error categories, and that it be no more -difficult to write portable code than system-specific code.

-

The operator<< overload for error_code eliminates a -misleading conversion to bool in code like cout << ec, where -ec is of type error_code. It is also useful in its own -right.

-

History

-

-N1975, Filesystem Library Proposal for TR2, accepted for Library Technical -Report 2 (TR2) at the Berlin meeting, included additional components to -supplement the Standard Library's Diagnostics clause. Since then, these error -reporting components have received wider public scrutiny and enhancements have -been made to the design. The enhanced version has been used by N2054, Networking -Library Proposal for TR2, demonstrating that these error reporting components -are useful beyond the original Filesystem Library.

-

The original proposal viewed error categories as a binary choice between -errno (i.e. POSIX-style) and the native operating system's error -codes. The proposed components now allow as many additional error categories as -are needed by either implementations or by users. The need to support additional -error categories, for example, occurs in some networking library implementations -because they are built on top of the POSIX getaddrinfo API that -uses error codes not based on errno.

-

Acknowledgements

-

Christopher Kohlhoff and Peter Dimov made important contributions to the -design. Comments and suggestions were also received from Pavel Vozenilek, -Gennaro Prota, Dave Abrahams, Jeff Garland, Iain Hanson, Oliver Kowalke, and -Oleg Abrosimov. Christopher Kohlhoff suggested several improvements to the N2066 -paper. Johan Nilsson's comments led to several of the refinements in N2066 .

-
- -

Revised -June 02, 2014 -

- -

© Copyright Beman Dawes, 1999

- -

Distributed under the Boost Software License, Version 1.0. -(See file LICENSE_1_0.txt -or  www.boost.org/LICENSE_1_0.txt)

- - - - \ No newline at end of file diff --git a/doc/reference.html b/doc/reference.html deleted file mode 100644 index 7ec0129..0000000 --- a/doc/reference.html +++ /dev/null @@ -1,834 +0,0 @@ - - - - - - - -System Library Reference - - - - - - - - - - -
- -boost.png (6897 bytes) - System Library -
- - - - - -
Boost Home    - Library Home   Tutorial   - Reference
- - - - - - - - -
- Contents
- Introduction
- C++11
- Macros
- Deprecated names
- Breaking changes
- Header <boost/system/error_code.hpp>
- Class error_category
-    Class error_category synopsis
-    Class error_category virtual members
-    Class error_category non-virtual members
-   Class error_category - non-member functions
-    Class error_category predefined objects
- Class error_code
-    Class error_code synopsis
-    Class error_code constructors
-    Class error_code modifiers
-    Class error_code observers
- Class error_condition
-    Class error_condition synopsis
-    Class error_condition constructors
-    Class error_condition modifiers
-    Class error_condition observers
- Function boost::throws()
- Non-member functions
- Header <boost/system/system_error.hpp>
-    Class system_error
-
- -

Introduction

- -

This reference documentation describes components that programs may use to report error conditions originating from the operating -system or other low-level application program interfaces.

-

Boost.System library components never change the value of -errno.

-

C++11

-

The library is documented to use several C++11 features, including -noexcept and explicit conversion operators. The actual implementation -uses C++11 features only when they are available, and otherwise falls back on -C++03 features.

-

Macros

-

Users may define the following macros if desired. Sensible defaults are -provided, so users may ignore these macros if they prefer.

- - - - - - - - - - - - - - - - - - - - - - - - - - -
Macro NameDefaultEffect if defined
BOOST_ERROR_CODE_HEADER_ONLYNot defined.The implementation is header-only, and the - Boost.System library is not built. Overrides other link and library macros.
BOOST_SYSTEM_DYN_LINKDefined if BOOST_ALL_DYN_LINK is defined, - otherwise not defined.Boost.System library is dynamically linked. If not defined, - static linking is assumed.
BOOST_SYSTEM_NO_LIBDefined if BOOST_ALL_NO_LIB is defined, - otherwise not defined.Boost.System library does not use the Boost auto-link - facility.
BOOST_SYSTEM_ENABLE_DEPRECATEDNot defined.Deprecated features are provided for compatibility.
-

Deprecated names

-

In the process of adding Boost.System to the C++11 standard library, the -C++ committee changed some names. To ease transition, Boost.System deprecates -the old names, but will provide them when the macro -BOOST_SYSTEM_ENABLE_DEPRECATED is defined.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Old usage, now deprecatedReplacement
get_generic_category()generic_category()
get_system_category()system_category()
namespace posixnamespace errc
namespace posix_errornamespace errc
enum posix_errnoenum errc_t
get_posix_category()generic_category()
posix_categorygeneric_category()
errno_ecatgeneric_category()
native_ecatsystem_category()
-

Breaking changes

-

Two static consts are replaced by functions. These are breaking changes best -fixed by globally adding () to these names to turn them into function calls.

- - - - - - - - - - - - - -
Old usage, now brokenReplacement
generic_categorygeneric_category()
system_categorysystem_category()
-

User-defined BOOST_POSIX_API and BOOST_WINDOWS_API macros are no longer supported.

-

Header <boost/system/error_code.hpp>

-

<boost/system/error_code.hpp> synopsis

-
-
namespace boost
-{
-  namespace system
-  {
-    class error_category;
-    const error_category &  system_category() noexcept;
-    const error_category &  generic_category() noexcept;
-
-    class error_code;
-    class error_condition;
-
-    //  "Concept" helpers
-    template< class T="" >
-      struct is_error_code_enum { static const bool value = false; };
-
-    template< class T="" >
-      struct is_error_condition_enum { static const bool value = false; };
-
-    //  generic error_conditions
-    namespace errc
-    {
-      enum errc_t
-      {
-        success = 0,
-        address_family_not_supported,   //EAFNOSUPPORT
-        address_in_use,                 //EADDRINUSE
-        address_not_available,          //EADDRNOTAVAIL
-        already_connected,              //EISCONN
-        argument_list_too_long,         //E2BIG
-        argument_out_of_domain,         //EDOM
-        bad_address,                    //EFAULT
-        bad_file_descriptor,            //EBADF
-        bad_message,                    //EBADMSG
-        broken_pipe,                    //EPIPE
-        connection_aborted,             //ECONNABORTED
-        connection_already_in_progress, //EALREADY
-        connection_refused,             //ECONNREFUSED
-        connection_reset,               //ECONNRESET
-        cross_device_link,              //EXDEV
-        destination_address_required,   //EDESTADDRREQ
-        device_or_resource_busy,        //EBUSY
-        directory_not_empty,            //ENOTEMPTY
-        executable_format_error,        //ENOEXEC
-        file_exists,                    //EEXIST
-        file_too_large,                 //EFBIG
-        filename_too_long,              //ENAMETOOLONG
-        function_not_supported,         //ENOSYS
-        host_unreachable,               //EHOSTUNREACH
-        identifier_removed,             //EIDRM
-        illegal_byte_sequence,          //EILSEQ
-        inappropriate_io_control_operation,//ENOTTY
-        interrupted,                    //EINTR
-        invalid_argument,               //EINVAL
-        invalid_seek,                   //ESPIPE
-        io_error,                       //EIO
-        is_a_directory,                 //EISDIR
-        message_size,                   //EMSGSIZE
-        network_down,                   //ENETDOWN
-        network_reset,                  //ENETRESET
-        network_unreachable,            //ENETUNREACH
-        no_buffer_space,                //ENOBUFS
-        no_child_process,               //ECHILD
-        no_link,                        //ENOLINK
-        no_lock_available,              //ENOLCK
-        no_message_available,           //ENODATA
-        no_message,                     //ENOMSG
-        no_protocol_option,             //ENOPROTOOPT
-        no_space_on_device,             //ENOSPC
-        no_stream_resources,            //ENOSR
-        no_such_device_or_address,      //ENXIO
-        no_such_device,                 //ENODEV
-        no_such_file_or_directory,      //ENOENT
-        no_such_process,                //ESRCH
-        not_a_directory,                //ENOTDIR
-        not_a_socket,                   //ENOTSOCK
-        not_a_stream,                   //ENOSTR
-        not_connected,                  //ENOTCONN
-        not_enough_memory,              //ENOMEM
-        not_supported,                  //ENOTSUP
-        operation_canceled,             //ECANCELED
-        operation_in_progress,          //EINPROGRESS
-        operation_not_permitted,        //EPERM
-        operation_not_supported,        //EOPNOTSUPP
-        operation_would_block,          //EWOULDBLOCK
-        owner_dead,                     //EOWNERDEAD
-        permission_denied,              //EACCES
-        protocol_error,                 //EPROTO
-        protocol_not_supported,         //EPROTONOSUPPORT
-        read_only_file_system,          //EROFS
-        resource_deadlock_would_occur,  //EDEADLK
-        resource_unavailable_try_again, //EAGAIN
-        result_out_of_range,            //ERANGE
-        state_not_recoverable,          //ENOTRECOVERABLE
-        stream_timeout,                 //ETIME
-        text_file_busy,                 //ETXTBSY
-        timed_out,                      //ETIMEDOUT
-        too_many_files_open_in_system,  //ENFILE
-        too_many_files_open,            //EMFILE
-        too_many_links,                 //EMLINK
-        too_many_synbolic_link_levels,  //ELOOP
-        value_too_large,                //EOVERFLOW
-        wrong_protocol_type             //EPROTOTYPE
-      };
-
-    } // namespace errc
-
-    template<> struct is_error_condition_enum<errc::errc_t>
-      { static const bool value = true; };
-
-    //  non-member functions
-
-    bool operator==( const error_code & lhs, const error_code & rhs ) noexcept;
-    bool operator==( const error_code & code, const error_condition & condition ) noexcept;
-    bool operator==( const error_condition & condition, const error_code & code ) noexcept;
-    bool operator==( const error_condition & lhs, const error_condition & rhs ) noexcept;
-
-    bool operator!=( const error_code & lhs, const error_code & rhs ) noexcept;
-    bool operator!=( const error_code & code, const error_condition & condition ) noexcept;
-    bool operator!=( const error_condition & condition, const error_code & code ) noexcept;
-    bool operator!=( const error_condition & lhs, const error_condition & rhs ) noexcept;
-
-    bool operator<( const error_code & lhs, const error_code & rhs ) noexcept;
-    bool operator<( const error_condition & lhs, const error_condition & rhs ) noexcept;
-
-    error_code make_error_code( errc::errc_t e ) noexcept;
-    error_condition make_error_condition( errc::errc_t e ) noexcept;
-
-    template <class charT, class traits>
-      std::basic_ostream<charT,traits>&
-        operator<<( basic_ostream<charT,traits>& os, const error_code & ec );
-
-    size_t hash_value( const error_code & ec );
-
-  } // namespace system
-
-  system::error_code & throws();
-    
-} // namespace boost
-
-

The value of each errc_t constant shall be the same as the -value of the <cerrno> macro shown in the above synopsis.

-

Users may specialize is_error_code_enum and -is_error_condition_enum templates to indicate that a type is eligible for -class error_code and error_condition automatic -conversions respectively.

- -
const error_category & system_category();
-
-

Returns: A reference to a error_category object - identifying errors originating from the operating system.

-
-
const error_category & generic_category();
-
-

Returns: A reference to a error_category object - identifying portable error conditions.

-
- -

Class error_category

-

The class error_category defines the base class for types used -to identify the source and encoding of a particular category of error code.

-

[Note: Classes may be derived from error_category -to support additional categories of errors. --end note]

-

The class error_category serves as a base class for types used -to identify the source and encoding of a particular category of error code. -Classes may be derived from error_category to support categories of -errors in addition to those defined in the Boost System library. Such classes -shall behave as specified in this subclause. [ Note: error_category -objects are passed by reference, and two such objects are equal if they have the -same address. This means that applications using custom error_category -types should create a single object of each such type. —end note ]

-

Class error_category synopsis

-
-
namespace boost
-{
-  namespace system
-  {
-    class error_category : public noncopyable
-    {
-    public:
-      virtual ~error_category();
-
-      virtual const char *     name() const noexcept = 0;
-      virtual string           message( int ev ) const = 0;
-      virtual error_condition  default_error_condition( int ev ) const noexcept;
-      virtual bool             equivalent( int code, const error_condition & condition )
-                                 const noexcept;
-      virtual bool             equivalent( const error_code & code, int condition ) const noexcept;
-
-      bool operator==( const error_category & rhs ) const noexcept;
-      bool operator!=( const error_category & rhs ) const noexcept;
-      bool operator< ( const error_category & rhs ) const noexcept;
-    };
-  }
-}
-
-

Class error_category virtual members

-

Classes derived from error_category shall behave as specified in -this subclause.

-
virtual const char * name() const noexcept =0;
-
-

Returns: a string naming the error category.

-
-
virtual string message( int ev ) const noexcept =0;
-
-

Returns: A string that describes the error denoted by - ev.

-
-
virtual error_condition default_error_condition( int ev ) const noexcept;
-
-

Returns:  error_condition( ev, *this ).

-
-

 [--Note: Derived classes will typically convert ev - to some portable error_category, such as generic_category(), - and return it as an error_condition for that category. --end - note]

-
-
-
virtual bool equivalent( int code, const error_condition & condition ) const noexcept;
-
-

Returns: default_error_condition( code ) == condition.

-
-
virtual bool equivalent( const error_code & code, int condition ) const noexcept;
-
-

Returns: *this == code.category() && code.value() == condition.

-
-

Class error_category non-virtual members

-
bool operator==( const error_category & rhs ) const noexcept;
-
-

Returns: this == &rhs.

-
-
bool operator!=( const error_category & rhs ) const noexcept;
-
-

Returns: this != &rhs.

-
- -
bool operator<( const error_category & rhs ) const noexcept;
-
-

Returns: std::less<const error_category*>()( this, &rhs  - noexcept).

-
-

[Note: std::less provides a total ordering for - pointers. --end note]

-
-
-

Class -error_code

-

The class error_code describes an object used to hold error code -values, such as those originating from the operating
-system or other low-level application program interfaces. [ Note: Class -error_code is an adjunct to error reporting by
-exception. —end note ]

-

Class -error_code synopsis

-
-
namespace boost
-{
-  namespace system
-  {
-    class error_code {
-    public:
-
-      // constructors:
-      error_code() noexcept;
-      error_code( val, const error_category & cat ) noexcept;
-      template <class ErrorCodeEnum>
-        error_code( ErrorCodeEnum e ) noexcept;
-
-      // modifiers:
-      void assign( int val, const error_category & cat ) noexcept;
-      template<typename ErrorCodeEnum>
-        error_code & operator=( ErrorCodeEnum val ) noexcept;
-      void clear() noexcept;
-
-      // observers:
-      int                    value() const noexcept;
-      cont error_category &  category() const noexcept;
-      error_condition        default_error_condition() const noexcept;
-      string                 message() const;
-      operator unspecified-bool-type() const;
-
-    private:
-      int val_;                     // exposition only
-      const error_category * cat_;  // exposition only
-    };
-  }
-}
-
-

Class -error_code constructors

-
error_code() noexcept;
-
-

Effects: Constructs an object of type error_code.

-

Postconditions: val_ == 0 && cat_ == &system_category().

-
-
error_code( int val, const error_category & cat ) noexcept;
-
-

Effects: Constructs an object of type error_code.

-

Postconditions: val_ == val && cat_ == &cat.

-
-
template <class ErrorCodeEnum>
-  error_code( ErrorCodeEnum val ) noexcept;
-
-

Effects: Constructs an object of type error_code.

-

Postconditions: *this == make_error_code( val ).

-

Remarks: This constructor shall not participate in overload - resolution unless is_error_code_enum<ErrorCodeEnum>::value is - true.

-
-

Class -error_code modifiers

-
void assign( int val, const error_category & cat ) noexcept;
-
-

Postconditions: val_ == val && cat_ == &cat.

-
-
template<typename ErrorCodeEnum>
-  error_code & operator=( ErrorCodeEnum val ) noexcept;
-
-

Postconditions: *this == make_error_code( val ).

-

Remarks: This operator shall not participate in overload resolution - unless is_error_code_enum<ErrorCodeEnum>::value is true.

-
-
void clear() noexcept;
-
-

postcondition: value() == 0 && category() == - system_category()

-
-

Class -error_code observers

- 
int value() const noexcept;
-
-

Returns: val_.

-
-
const error_category & category() const noexcept;
-
-

Returns: *cat_.

-
- 
error_condition default_error_condition() const noexcept;
-
-

Returns:  category().default_error_condition( value()).

-
- 
string message() const;
-
-

Returns:  category().message( value()).

-

Throws: Nothing.

-
-
operator unspecified-bool-type() const;
-
-

Returns: if value() != 0, returns a value that will evaluate -true in a boolean context; otherwise, returns a value that will -evaluate false in a boolean context. The value type returned shall -not be convertible to int.

-

Throws: nothing.

-

[Note: This conversion can be used in contexts where a bool -is expected ( e.g., an if condition ); however, implicit conversions -( e.g., to int) that can occur with bool are not -allowed, eliminating some sources of user error. One possible implementation -choice for this type is pointer-to-member. --end note ]

-
-

Class error_condition

-

The class error_condition describes an object used to hold -values identifying error conditions. [ Note: error_condition -values are portable abstractions, while error_code values are -implementation specific. --end note ]

-

Class error_condition synopsis

-
-
namespace boost
-{
-  namespace system
-  {
-    class error_condition
-    {
-    public:
-
-      // constructors:
-      error_condition() noexcept;
-      error_condition( int val, const error_category & cat ) noexcept;
-      template <class ErrorConditionEnum>
-        error_condition( errorConditionEnum val ) noexcept;
-
-      // modifiers:
-      void assign( int val, const error_category & cat ) noexcept;
-      template<typename ErrorConditionEnum>
-        error_condition & operator=( ErrorConditionEnum val ) noexcept;
-      void clear() noexcept;
-
-      // observers:
-      int value() const noexcept;
-      const error_category & category() const noexcept;
-      string message() const;
-      operator unspecified-bool-type () const noexcept;
-
-    private:
-      int val_;                      // exposition only
-      const error_category * cat_;   // exposition only
-    };
-  }
-}
-
-

Class error_condition -constructors

-
error_condition() noexcept;
-
-

Effects: Constructs an object of type error_condition.

-

Postconditions: val_ == 0 and cat_ == &generic_category().

-
-
error_condition( int val, const error_category & cat ) noexcept;
-
-

Effects: Constructs an object of type error_condition.

-

Postconditions: val_ == val and cat_ == &cat.

-
-
template <class ErrorConditionEnum>
-  error_condition( ErrorConditionEnum e ) noexcept;
-
-

Effects: Constructs an object of type error_condition.

-

Postconditions: *this == make_error_condition(e).

-

Remarks: This constructor shall not participate in overload - resolution unless is_error_condition_enum<ErrorConditionEnum>::value - is true.

-
-

Class error_condition -modifiers

-
void assign( int val, const error_category & cat ) noexcept;
-
-

Postconditions: val_ == val and cat_ == &cat.

-
-
template<typename ErrorConditionEnum>
-  error_condition & operator=( ErrorConditionEnum e ) noexcept;
-
-

Postconditions: *this == make_error_condition( e ).

-

Returns: *this.

-

Remarks: This operator shall not participate in overload resolution - unless is_error_condition_enum<ErrorConditionEnum>::value is - true.

-
-
void clear() noexcept;
-
-

Postcondition: value() == 0 && category() == generic_category()

-
-

Class error_condition -observers

-
int value() const noexcept;
-
-

Returns: val_.

-
-
const error_category & category() const noexcept;
-
-

Returns: *cat_.

-
-
string message() const;
-
-

Returns: category().message( value() ).

-
-
operator unspecified-bool-type () const;
-
-

Returns: If value() != 0, returns a value that will - evaluate true in a boolean context; otherwise, returns a value - that will evaluate false. The return type shall not be - convertible to int.

-

Throws: Nothing.

-

 [ Note: This conversion can be used in contexts where a bool - is expected ( e.g., an if condition ); however, implicit conversions ( e.g., to - int) that can occur with bool are not allowed, - eliminating some sources of user error. One possible implementation choice for - this type is pointer to member. --end note ]

-
-

Non-member functions

- 
bool operator==( const error_code & lhs, const error_code & rhs ) noexcept;
-
-

Returns: lhs.category() == rhs.category() && lhs.value() == - rhs.value().

-
-
bool operator==( const error_code & code, const error_condition & condition ) noexcept;
-bool operator==( const error_condition & condition, const error_code & code ) noexcept;
-
-

Returns: code.category().equivalent( code.value(), condition )
- || condition.category().equivalent( code, condition.value() ).

-
-
bool operator==( const error_condition & lhs, const error_condition & rhs ) noexcept;
-
-

Returns: lhs.category() == rhs.category() && lhs.value() == - rhs.value().

-
-
bool operator!=( const error_code & lhs, const error_code & rhs ) noexcept;
-
-

Returns: !(lhs == rhs ).

-
-
bool operator!=( const error_code & code, const error_condition & condition ) noexcept;
-bool operator!=( const error_condition & condition, const error_code & code ) noexcept;
-
-

Returns: !( code ==  condition ).

-
-
bool operator!=( const error_condition & lhs, const error_condition & rhs ) noexcept;
-
-

Returns: !(lhs == rhs ).

-
-
bool operator<( const error_code & lhs, const error_code & rhs ) noexcept;
-
-

Returns: lhs.category() < rhs.category()
-   || (lhs.category() == rhs.category() && lhs.value() < rhs.value()).

-
-
bool operator<( const error_condition & lhs, const error_condition & rhs ) noexcept;
-
-

Returns: lhs.category() < rhs.category()
-   || (lhs.category() == rhs.category() && lhs.value() < rhs.value()).

-
-
error_code make_error_code( errc::errc_t e ) noexcept;
-
-

Returns: error_code( e, generic_category()).

-
-
error_condition make_error_condition( errc::errc_t e ) noexcept;
-
-

Returns: error_condition( static_cast<int>( e ), generic_category()).

-
- -
template <class charT, class traits>
-  std::basic_ostream<charT,traits>&
-    operator<<( basic_ostream<charT,traits>& os, const error_code & ec );
-
-

Effects: os << ec.category().name() << ':' << ec.value().

-

Returns: os.

-
-
size_t hash_value( const error_code & ec );
-
-

Returns:  A hash value representing ec.

-
- -

Function boost::throws()

- - 
system::error_code& throws();
-
-

Returns: A system::error_code reference -for use in some user-defined function signature as a "throw on error" tag.

-

Remark: The only valid use for the returned reference is to test its -address for equality or inequality to the address of the reference returned by -another call to throws(). The returned reference itself has been poisoned so -that an attempt to dereference it will fail.

-

[Example: Example of a function that uses the throws() idiom:

-
- 
int divide(int dividend, int divisor,
-           boost::system::error_code& ec = boost::throws())
-{
-  if (divisor == 0)                             // is there an error?
-  {
-    if (&ec == &boost::throws())                // throw on error
-      throw "oops!";                            // whatever exception you prefer
-    ec = error_code(EDOM, generic_category());  // report error via error_code
-    return 0;
-  }
-
-  if (&ec != &boost::throws())                  // error reporting via error_code
-    ec.clear();
-  return dividend / divisor;
-}
-
-

— end Example]

-
- -

Header <boost/system/system_error.hpp>

- -

Class -system_error

-

The class system_error describes an exception object used to -report errors that have an associated error_code. Such errors typically originate from operating system or other low-level -application program interfaces.

-
-
namespace boost
-{
-  namespace system
-  {
-    class system_error : public std::runtime_error
-    {
-    public:
-      system_error( error_code ec );
-      system_error( error_code ec, const char * what_arg );
-      system_error( error_code ec, const std::string & what_arg );
-      system_error( int ev, const error_category & ecat,
-                    const char * what_arg );
-      system_error( int ev, const error_category & ecat,
-                    const std::string & what_arg );
-      system_error( int ev, const error_category & ecat);
-
-      const error_code & code() const throw();
-      const char *       what() const throw();
-    };
-  }
-}
-
-
system_error( error_code ec );
-
-

Effects: Constructs an object of class system_error.

-

Postcondition: code() == ec
-  && std::strcmp( this->runtime_error::what(), "" ) == 0

-
-
system_error( error_code ec, const char * what_arg );
-
-

Effects: Constructs an object of class system_error.

-

Postcondition: code() == ec
-  && std::strcmp( this->runtime_error::what(), what_arg ) == 0

-
-
system_error( error_code ec, const std::string & what_arg );
-
-

Effects: Constructs an object of class system_error.

-

Postcondition: code() == ec
-  && std::strcmp( this->runtime_error::what(), what_arg.c_str() ) == 0

-
-
system_error( int ev, const error_category & ecat,
-             const char * what_arg );
-
-

Effects: Constructs an object of class system_error.

-

Postcondition: code() == error_code( ev, ecat )
-  && std::strcmp( this->runtime_error::what(), what_arg ) == 0

-
-
system_error( int ev, const error_category & ecat,
-             const std::string & what_arg );
-
-

Effects: Constructs an object of class system_error.

-

Postcondition: code() == error_code( ev, ecat )
-  && std::strcmp( this->runtime_error::what(), what_arg.c_str() ) == 0

-
-
system_error( int ev, const error_category & ecat );
-
-

Effects: Constructs an object of class system_error.

-

Postcondition: code() == error_code( ev, ecat )
-  && std::strcmp( this->runtime_error::what(), "" ) == 0

-
-
const error_code & code() const;
-
-

Returns: ec or error_code( ev, ecat ), from - the constructor, as appropriate.

-
-
const char * what() const;
-
-

Returns: A string incorporating - this->runtime_error::what() and - code.message().

-
-
- -

Revised -September 07, 2017 -

- -

© Copyright Beman Dawes, 2006, 2007, 2008, 2013

- -

Distributed under the Boost Software License, Version 1.0. See -www.boost.org/LICENSE_1_0.txt

- - - - \ No newline at end of file diff --git a/index.html b/index.html index 7fe9a07..3f89f4f 100644 --- a/index.html +++ b/index.html @@ -1,14 +1,15 @@ - + Automatic redirection failed, please go to -doc/index.html. -
-

© Copyright Beman Dawes, 2003

-

Distribution under the Boost Software License, Version 1.0. -(See accompanying file LICENSE_1_0.txt or copy at -www.boost.org/LICENSE_1_0.txt)

+doc/html/system.html. - \ No newline at end of file + +