enum class errc;
(since C++11)The scoped enumeration std::errc defines the values of portable error conditions that correspond to the POSIX error codes.
address_family_not_supported EAFNOSUPPORT address_in_use EADDRINUSE address_not_available EADDRNOTAVAIL already_connected EISCONN argument_list_too_long E2BIG argument_out_of_domain EDOM bad_address EFAULT bad_file_descriptor EBADF bad_message EBADMSG broken_pipe EPIPE connection_aborted ECONNABORTED connection_already_in_progress EALREADY connection_refused ECONNREFUSED connection_reset ECONNRESET cross_device_link EXDEV destination_address_required EDESTADDRREQ device_or_resource_busy EBUSY directory_not_empty ENOTEMPTY executable_format_error ENOEXEC file_exists EEXIST file_too_large EFBIG filename_too_long ENAMETOOLONG function_not_supported ENOSYS host_unreachable EHOSTUNREACH identifier_removed EIDRM illegal_byte_sequence EILSEQ inappropriate_io_control_operation ENOTTY interrupted EINTR invalid_argument EINVAL invalid_seek ESPIPE io_error EIO is_a_directory EISDIR message_size EMSGSIZE network_down ENETDOWN network_reset ENETRESET network_unreachable ENETUNREACH no_buffer_space ENOBUFS no_child_process ECHILD no_link ENOLINK no_lock_available ENOLCK no_message_available (deprecated) ENODATA no_message ENOMSG no_protocol_option ENOPROTOOPT no_space_on_device ENOSPC no_stream_resources (deprecated) ENOSR no_such_device_or_address ENXIO no_such_device ENODEV no_such_file_or_directory ENOENT no_such_process ESRCH not_a_directory ENOTDIR not_a_socket ENOTSOCK not_a_stream (deprecated) ENOSTR not_connected ENOTCONN not_enough_memory ENOMEM not_supported ENOTSUP operation_canceled ECANCELED operation_in_progress EINPROGRESS operation_not_permitted EPERM operation_not_supported EOPNOTSUPP operation_would_block EWOULDBLOCK owner_dead EOWNERDEAD permission_denied EACCES protocol_error EPROTO protocol_not_supported EPROTONOSUPPORT read_only_file_system EROFS resource_deadlock_would_occur EDEADLK resource_unavailable_try_again EAGAIN result_out_of_range ERANGE state_not_recoverable ENOTRECOVERABLE stream_timeout (deprecated) ETIME text_file_busy ETXTBSY timed_out ETIMEDOUT too_many_files_open_in_system ENFILE too_many_files_open EMFILE too_many_links EMLINK too_many_symbolic_link_levels ELOOP value_too_large EOVERFLOW wrong_protocol_type EPROTOTYPE [edit] Non-member functions [edit] Helper classes [edit] Example
#include <filesystem>
#include <fstream>
#include <iomanip>
#include <iostream>
#include <string>
#include <system_error>
#include <thread>
void print_error(const std::string& details, std::error_code error_code)
{
std::string value_name;
if (error_code == std::errc::invalid_argument)
value_name = "std::errc::invalid_argument";
if (error_code == std::errc::no_such_file_or_directory)
value_name = "std::errc::no_such_file_or_directory";
if (error_code == std::errc::is_a_directory)
value_name = "std::errc::is_a_directory";
if (error_code == std::errc::permission_denied)
value_name = "std::errc::permission_denied";
std::cout << details << ":\n "
<< std::quoted(error_code.message())
<< " (" << value_name << ")\n\n";
}
void print_errno(const std::string& details, int errno_value = errno)
{
print_error(details, std::make_error_code(std::errc(errno_value)));
}
int main()
{
std::cout << "Detaching a not-a-thread...\n";
try
{
std::thread().detach();
}
catch (const std::system_error& e)
{
print_error("Error detaching empty thread", e.code());
}
std::cout << "Opening nonexistent file...\n";
std::ifstream nofile{"nonexistent-file"};
if (!nofile.is_open())
print_errno("Error opening nonexistent file for reading");
std::cout << "Reading from directory as a file...\n";
std::filesystem::create_directory("dir");
std::ifstream dir_stream{"dir"};
[[maybe_unused]] char c = dir_stream.get();
if (!dir_stream.good())
print_errno("Error reading data from directory");
std::cout << "Open read-only file for writing...\n";
std::fstream{"readonly-file", std::ios::out};
std::filesystem::permissions("readonly-file", std::filesystem::perms::owner_read);
std::fstream write_readonly("readonly-file", std::ios::out);
if (!write_readonly.is_open())
print_errno("Error opening read-only file for writing");
}
Possible output:
Detaching a not-a-thread... Error detaching empty thread: "Invalid argument" (std::errc::invalid_argument) Opening nonexistent file... Error opening nonexistent file for reading: "No such file or directory" (std::errc::no_such_file_or_directory) Reading from directory as a file... Error reading data from directory: "Is a directory" (std::errc::is_a_directory) Open read-only file for writing... Error opening read-only file for writing: "Permission denied" (std::errc::permission_denied)[edit] Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR Applied to Behavior as published Correct behavior LWG 3869 C++11 the member constantsno_message_available,
no_stream_resources, not_a_stream and stream_timeout
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4