NAME

       std::basic_istream< _CharT, _Traits >::sentry -

SYNOPSIS

   Public Types
       typedef
           __istream_type::__ctype_type __ctype_type"
       typedef _Traits::int_type __int_type
       typedef basic_istream< _CharT,
           _Traits > __istream_type"
       typedef basic_streambuf
           < _CharT, _Traits > __streambuf_type"
       typedef _Traits traits_type

   Public Member Functions
       sentry (basic_istream< _CharT, _Traits > &__is, bool __noskipws=false)
       operator bool () const

Detailed Description

   template<typename _CharT, typename _Traits = char_traits<_CharT>>class std::basic_istream< _CharT, _Traits
       >::sentry
       Performs setup work for input streams.

       Objects of this class are created before all of the standard extractors are run. It is responsible for
       exception-safe prefix and suffix operations, although only prefix actions are currently required by the
       standard.

       Definition at line 638 of file istream.

Member Typedef Documentation

   template<typename _CharT, typename _Traits = char_traits<_CharT>> typedef _Traits std::basic_istream< _CharT,
       _Traits >::sentry::traits_type
       Easy access to dependant types.

       Definition at line 645 of file istream.

Constructor & Destructor Documentation

   template<typename _CharT, typename _Traits = char_traits<_CharT>> std::basic_istream< _CharT, _Traits
       >::sentry::sentry (basic_istream< _CharT, _Traits > &__is, bool__noskipws = false) [explicit]
       The constructor performs all the work.

       Parameters:
           is The input stream to guard.
           noskipws Whether to consume whitespace or not.

       If the stream state is good (is.good() is true), then the following actions are performed, otherwise the
       sentry state is false (not okay) and failbit is set in the stream state.

       The sentry's preparatory actions are:

       1.  if  the  stream  is  tied  to an output stream, is.tie()->flush() is called to synchronize the output
           sequence

       2.  if noskipws is false, and ios_base::skipws is set in is.flags(), the  sentry  extracts  and  discards
           whitespace  characters from the stream. The currently imbued locale is used to determine whether each
           character is whitespace.

       If the stream state is still good, then the sentry state becomes true (okay).

       Definition at line 49 of file istream.tcc.

       References std::ios_base::eofbit, std::ios_base::failbit, std::ios_base::flags(), std::basic_ios< _CharT,
       _Traits >::good(), std::ios_base::goodbit, std::__ctype_abstract_base<  _CharT  >::is(),  std::basic_ios<
       _CharT,  _Traits >::rdbuf(), std::basic_ios< _CharT, _Traits >::setstate(), std::basic_streambuf< _CharT,
       _Traits  >::sgetc(),  std::ios_base::skipws,  std::basic_streambuf<  _CharT,  _Traits  >::snextc(),   and
       std::basic_ios< _CharT, _Traits >::tie().

Member Function Documentation

   template<typename  _CharT,  typename  _Traits  =  char_traits<_CharT>>  std::basic_istream<  _CharT,  _Traits
       >::sentry::operator bool () const [inline],  [explicit]
       Quick status checking.

       Returns:
           The sentry state.

       For ease of use, sentries may be converted to booleans. The return value is  that  of  the  sentry  state
       (true == okay).

       Definition at line 686 of file istream.

Author

       Generated automatically by Doxygen for libstdc++ from the source code.

libstdc++                                        Thu Mar 20 2std::basic_istream< _CharT, _Traits >::sentry(3cxx)