std::filesystem::filesystem_error::what

 

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filesystem::path filesystem::filesystem_error filesystem::directory_entry filesystem::directory_iterator filesystem::recursive_directory_iterator    filesystem::file_status filesystem::space_info	filesystem::file_type filesystem::file_time_type filesystem::perms filesystem::perm_options filesystem::copy_options filesystem::directory_options
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filesystem::absolute filesystem::canonicalfilesystem::weakly_canonical filesystem::relativefilesystem::proximate filesystem::copy filesystem::copy_file filesystem::copy_symlink filesystem::create_directory filesystem::create_directories filesystem::create_hard_link filesystem::create_symlink filesystem::create_directory_symlink filesystem::current_path filesystem::temp_directory_path	filesystem::exists filesystem::equivalent filesystem::file_size filesystem::hard_link_count filesystem::last_write_time filesystem::permissions filesystem::read_symlink filesystem::remove filesystem::remove_all filesystem::rename filesystem::resize_file filesystem::space filesystem::status filesystem::symlink_status
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filesystem::is_block_file filesystem::is_character_file filesystem::is_directory filesystem::is_empty filesystem::status_known	filesystem::is_fifo filesystem::is_other filesystem::is_regular_file filesystem::is_socket filesystem::is_symlink

 

filesystem_error

成员函数

filesystem_error::filesystem_error

filesystem_error::operator=

filesystem_error::path1filesystem_error::path2

filesystem_error::what

继承自 std::system_error

system_error::code

 

constchar* what()constnoexcept override;		(C++17 起)

返回解释性字节字符串。此解释性字符串含有在构造时传递的解释字符串。鼓励实现在返回的字符串中包含原生格式的 path1() 和 path2() 的路径名，以及 std::system_error::what() 字符串。

参数

（无）

返回值

包含构造时所传递的解释字符串的 C 风格解释字节字符串。

示例

运行此代码

#include <cstdio>#include <filesystem>#include <iostream>#include <string_view>namespace fs = std::filesystem;   void explain(std::string_view note, fs::filesystem_errorconst& ex){std::cout<< note <<" exception:\n"<<"what(): "<< ex.what()<<'\n'<<"path1(): "<< ex.path1()<<", path2(): "<< ex.path2()<<"\n\n";}   int main(){try{std::filesystem::rename("/dev", "/null");}catch(fs::filesystem_errorconst& ex){ explain("fs::rename()", ex);}   for(autoconst path :{"/bool", "/bin/cat", "/bin/mouse"})try{std::filesystem::create_directory(path);}catch(fs::filesystem_errorconst& ex){ explain("fs::create_directory()", ex);}}

可能的输出：

fs::rename() exception: what(): filesystem error: cannot rename: Permission denied [/dev] [/null] path1(): "/dev", path2(): "/null"   fs::create_directory() exception: what(): filesystem error: cannot create directory: Permission denied [/bool] path1(): "/bool", path2(): ""   fs::create_directory() exception: what(): filesystem error: cannot create directory: File exists [/bin/cat] path1(): "/bin/cat", path2(): ""   fs::create_directory() exception: what(): filesystem error: cannot create directory: Read-only file system [/bin/mouse] path1(): "/bin/mouse", path2(): ""