我编写了一段代码，使用 boost 将输出写入 gz 文件。
class foo() {
std::ofstream traceOut;
struct traceRec {
traceRec(uint64_t c) : cycle(c) {};
uint64_t cycle;
};
void writeTrace(traceRec &rec)
{
try {
boost::iostreams::filtering_istream in;
in.push(boost::iostreams::gzip_decompressor());
in.push(traceOut); // ERROR
std::cout << rec.cycle << std::endl;
}
catch(const boost::iostreams::gzip_error& e) {
std::cout << e.what() << '\n';
}
}
void init() {
traceOut.open("log.gz", std::ios_base::in | std::ios_base::binary);
}
void bar() {
traceRec rec (1000);
writeTrace(rec);
}
};
编译时出现这个错误
/opt/boost_1_33_1/boost/iostreams/chain.hpp: In member function ‘void boost::iostreams::detail::chain_client<Chain>::push(std::basic_ostream<_CharT2, _Traits2>&, int, int) [with CharType = char, TraitsType = std::char_traits<char>, Chain = boost::iostreams::chain<boost::iostreams::input, char,
std::char_traits<char>, std::allocator<char> >]’:
test.cpp: instantiated from here
/opt/boost_1_33_1/boost/iostreams/chain.hpp:472: error: invalid application of ‘sizeof’ to incomplete type ‘boost::STATIC_ASSERTION_FAILURE<false>’
/opt/boost_1_33_1/boost/iostreams/traits.hpp: At global scope:
/opt/boost_1_33_1/boost/iostreams/traits.hpp: In instantiation of ‘boost::iostreams::detail::member_category<mpl_::void_>’:
/opt/boost_1_33_1/boost/mpl/eval_if.hpp:38: instantiated from ‘boost::mpl::eval_if<boost::iostreams::is_std_io<mpl_::void_>, boost::iostreams::select<boost::iostreams::is_iostream<mpl_::void_>, boost::iostreams::iostream_tag, boost::iostreams::is_istream<mpl_::void_>, boost::iostreams::istream_tag, boost::iostreams::is_ostream<mpl_::void_>, boost::iostreams::ostream_tag, boost::iostreams::is_streambuf<mpl_::void_>, boost::iostreams::streambuf_tag, mpl_::bool_<true>, mpl_::void_, mpl_::bool_<true>, mpl_::void_, mpl_::bool_<true>, mpl_::void_, mpl_::bool_<true>, mpl_::void_, mpl_::bool_<true>, mpl_::void_, mpl_::bool_<true>, mpl_::void_>, boost::iostreams::detail::member_category<mpl_::void_> >’
....
这是什么意思？
最佳答案
请看this , push() 方法必须接收流而不是任意对象
EDIT1(以下评论交流)
将 traceOut 的类型更改为 std::ifstream 解决了构建问题(至少使用 boost 1.52)
关于c++ - 用 boost 写一个 gz 流，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/15394609/