c++11 std::call_once只调用一次函数，类似单例模式std_call_oncestd::call_once 保证函数或者一些代码段在并发或者多线程的情况下，始终只会被执行一次，Demo如下： include <iostream> include <thread>static std::once_flag g_once_flag std::call_once 保证...

Undefined reference to symbol X509_freeundefined-reference-to-symbol-x509-freeUndefined reference to symbol X509_free 编译错误的解决方法：链接库中增加 -lcrypto，而非 -lcrypt参考：https: stackoverflow com questions 33215936 undefined-reference-to-symbol-x509-freeUndefined refer...

【解决】File does not reside within any path specified using proto_pathfile-does-not-reside-within-any-path-specified-using-proto-path使用protoc编译 proto文件时报错： main test test proto: File does not reside within any path specified using --proto_path (or -I) You must specify ...

eclipse git插件设置代理eclipse_git_proxyeclipse git插件设置代理本质就是eclipse网络代理设置，在"Network Connections"网络相关地方设置才有效，而设置Git -> Configuration是无效的。设置方法如下：解决~eclipse git插件设置代理本质就是eclipse网...

libunwind链接时报错：undefined reference to `_Ux86_64_init_local'编译安装libunwind后，代码编译链接时报错：undefined reference to `_Ux86_64_init_local& 39;，链接选项加了 -lunwind，仍然报错。原因：编译出来的libunwind拆分成了很多个 编译安装libunwi...

[解决]Missing Constraint: Bundle-RequiredExecutionEnvironment: J2SE-1.5eclipse-Missing-Constraint原因：eclipse版本太老了，java版本太新了不匹配导致。解决：安装最新的eclipse，地址：https: www eclipse org downloads 参考：https: www eclipse org forums index php t 1...

OpenSuSE 安装dtraceOpenSuSE-dtrace-install官网：https: software opensuse org搜索 dtrace，选择：找到指定的版本ymp文件，这里以15 1为例：OCICLI https: software opensuse org ymp home:Dead_Mozay:gst openSUSE_Leap_15 1 systemtap-dtrace ymp--End--官网：https://software.opens...

[解决]Missing Constraint: Bundle-RequiredExecutionEnvironment: J2SE-1.5eclipse-Missing-Constraint原因：eclipse版本太老了，java版本太新了不匹配导致。解决：安装最新的eclipse，地址：https: www eclipse org downloads 参考：https: www eclipse org forums index php t 1...

OpenSuSE 安装dtraceOpenSuSE-dtrace-install官网：https: software opensuse org搜索 dtrace，选择：找到指定的版本ymp文件，这里以15 1为例：OCICLI https: software opensuse org ymp home:Dead_Mozay:gst openSUSE_Leap_15 1 systemtap-dtrace ymp--End--官网：https://software.opens...

[解决]Missing Constraint: Bundle-RequiredExecutionEnvironment: J2SE-1.5eclipse-Missing-Constraint原因：eclipse版本太老了，java版本太新了不匹配导致。解决：安装最新的eclipse，地址：https: www eclipse org downloads 参考：https: www eclipse org forums index php t 1...