📄 ostream
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* Tries to insert @a c.
*
* @note This function is not overloaded on signed char and
* unsigned char.
*/
__ostream_type&
put(char_type __c);
// Core write functionality, without sentry.
void
_M_write(const char_type* __s, streamsize __n)
{
streamsize __put = this->rdbuf()->sputn(__s, __n);
if (__put != __n)
this->setstate(ios_base::badbit);
}
/**
* @brief Character string insertion.
* @param s The array to insert.
* @param n Maximum number of characters to insert.
* @return *this
*
* Characters are copied from @a s and inserted into the stream until
* one of the following happens:
*
* - @a n characters are inserted
* - inserting into the output sequence fails (in this case, badbit
* will be set in the stream's error state)
*
* @note This function is not overloaded on signed char and
* unsigned char.
*/
__ostream_type&
write(const char_type* __s, streamsize __n);
//@}
/**
* @brief Synchronizing the stream buffer.
* @return *this
*
* If @c rdbuf() is a null pointer, changes nothing.
*
* Otherwise, calls @c rdbuf()->pubsync(), and if that returns -1,
* sets badbit.
*/
__ostream_type&
flush();
// [27.6.2.4] seek members
/**
* @brief Getting the current write position.
* @return A file position object.
*
* If @c fail() is not false, returns @c pos_type(-1) to indicate
* failure. Otherwise returns @c rdbuf()->pubseekoff(0,cur,out).
*/
pos_type
tellp();
/**
* @brief Changing the current write position.
* @param pos A file position object.
* @return *this
*
* If @c fail() is not true, calls @c rdbuf()->pubseekpos(pos). If
* that function fails, sets failbit.
*/
__ostream_type&
seekp(pos_type);
/**
* @brief Changing the current write position.
* @param off A file offset object.
* @param dir The direction in which to seek.
* @return *this
*
* If @c fail() is not true, calls @c rdbuf()->pubseekoff(off,dir).
* If that function fails, sets failbit.
*/
__ostream_type&
seekp(off_type, ios_base::seekdir);
protected:
explicit
basic_ostream() { }
};
/**
* @brief Performs setup work for output streams.
*
* Objects of this class are created before all of the standard
* inserters are run. It is responsible for "exception-safe prefix and
* suffix operations." Additional actions may be added by the
* implementation, and we list them in
* http://gcc.gnu.org/onlinedocs/libstdc++/17_intro/howto.html#5
* under [27.6] notes.
*/
template <typename _CharT, typename _Traits>
class basic_ostream<_CharT, _Traits>::sentry
{
// Data Members:
bool _M_ok;
basic_ostream<_CharT,_Traits>& _M_os;
public:
/**
* @brief The constructor performs preparatory work.
* @param os The output stream to guard.
*
* If the stream state is good (@a os.good() is true), then if the
* stream is tied to another output stream, @c is.tie()->flush()
* is called to synchronize the output sequences.
*
* If the stream state is still good, then the sentry state becomes
* true ("okay").
*/
explicit
sentry(basic_ostream<_CharT,_Traits>& __os);
/**
* @brief Possibly flushes the stream.
*
* If @c ios_base::unitbuf is set in @c os.flags(), and
* @c std::uncaught_exception() is true, the sentry destructor calls
* @c flush() on the output stream.
*/
~sentry()
{
// XXX MT
if (_M_os.flags() & ios_base::unitbuf && !uncaught_exception())
{
// Can't call flush directly or else will get into recursive lock.
if (_M_os.rdbuf() && _M_os.rdbuf()->pubsync() == -1)
_M_os.setstate(ios_base::badbit);
}
}
/**
* @brief Quick status checking.
* @return The sentry state.
*
* For ease of use, sentries may be converted to booleans. The
* return value is that of the sentry state (true == okay).
*/
operator bool() const
{ return _M_ok; }
};
// [27.6.2.5.4] character insertion templates
//@{
/**
* @brief Character inserters
* @param out An output stream.
* @param c A character.
* @return out
*
* Behaves like one of the formatted arithmetic inserters described in
* std::basic_ostream. After constructing a sentry object with good
* status, this function inserts a single character and any required
* padding (as determined by [22.2.2.2.2]). @c out.width(0) is then
* called.
*
* If @a c is of type @c char and the character type of the stream is not
* @c char, the character is widened before insertion.
*/
template<typename _CharT, typename _Traits>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __out, _CharT __c);
template<typename _CharT, typename _Traits>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __out, char __c)
{ return (__out << __out.widen(__c)); }
// Specialization
template <class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __out, char __c);
// Signed and unsigned
template<class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __out, signed char __c)
{ return (__out << static_cast<char>(__c)); }
template<class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __out, unsigned char __c)
{ return (__out << static_cast<char>(__c)); }
//@}
//@{
/**
* @brief String inserters
* @param out An output stream.
* @param s A character string.
* @return out
* @pre @a s must be a non-NULL pointer
*
* Behaves like one of the formatted arithmetic inserters described in
* std::basic_ostream. After constructing a sentry object with good
* status, this function inserts @c traits::length(s) characters starting
* at @a s, widened if necessary, followed by any required padding (as
* determined by [22.2.2.2.2]). @c out.width(0) is then called.
*/
template<typename _CharT, typename _Traits>
basic_ostream<_CharT, _Traits>&
operator<<(basic_ostream<_CharT, _Traits>& __out, const _CharT* __s);
template<typename _CharT, typename _Traits>
basic_ostream<_CharT, _Traits> &
operator<<(basic_ostream<_CharT, _Traits>& __out, const char* __s);
// Partial specializationss
template<class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __out, const char* __s);
// Signed and unsigned
template<class _Traits>
basic_ostream<char, _Traits>&
operator<<(basic_ostream<char, _Traits>& __out, const signed char* __s)
{ return (__out << reinterpret_cast<const char*>(__s)); }
template<class _Traits>
basic_ostream<char, _Traits> &
operator<<(basic_ostream<char, _Traits>& __out, const unsigned char* __s)
{ return (__out << reinterpret_cast<const char*>(__s)); }
//@}
// [27.6.2.7] standard basic_ostream manipulators
/**
* @brief Write a newline and flush the stream.
*
* This manipulator is often mistakenly used when a simple newline is
* desired, leading to poor buffering performance. See
* http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#2 for more
* on this subject.
*/
template<typename _CharT, typename _Traits>
basic_ostream<_CharT, _Traits>&
endl(basic_ostream<_CharT, _Traits>& __os)
{ return flush(__os.put(__os.widen('\n'))); }
/**
* @brief Write a null character into the output sequence.
*
* "Null character" is @c CharT() by definition. For CharT of @c char,
* this correctly writes the ASCII @c NUL character string terminator.
*/
template<typename _CharT, typename _Traits>
basic_ostream<_CharT, _Traits>&
ends(basic_ostream<_CharT, _Traits>& __os)
{ return __os.put(_CharT()); }
/**
* @brief Flushes the output stream.
*
* This manipulator simply calls the stream's @c flush() member function.
*/
template<typename _CharT, typename _Traits>
basic_ostream<_CharT, _Traits>&
flush(basic_ostream<_CharT, _Traits>& __os)
{ return __os.flush(); }
} // namespace std
#ifndef _GLIBCXX_EXPORT_TEMPLATE
# include <bits/ostream.tcc>
#endif
#endif /* _GLIBCXX_OSTREAM */
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