Standard library header <cerrno>
From cppreference.com
                    
                                        
                    
                    
                                                            
                    This header was originally in the C standard library as <errno.h>.
This header is part of the error handling library.
[edit] Macros
| macro which expands to POSIX-compatible thread-local error number variable (macro variable) | |
| E2BIG (C++11) | Argument list too long (macro constant) | 
| EACCES (C++11) | Permission denied (macro constant) | 
| EADDRINUSE (C++11) | Address in use (macro constant) | 
| EADDRNOTAVAIL (C++11) | Address not available (macro constant) | 
| EAFNOSUPPORT (C++11) | Address family not supported (macro constant) | 
| EAGAIN (C++11) | Resource unavailable, try again (macro constant) | 
| EALREADY (C++11) | Connection already in progress (macro constant) | 
| EBADF (C++11) | Bad file descriptor (macro constant) | 
| EBADMSG (C++11) | Bad message (macro constant) | 
| EBUSY (C++11) | Device or resource busy (macro constant) | 
| ECANCELED (C++11) | Operation canceled (macro constant) | 
| ECHILD (C++11) | No child processes (macro constant) | 
| ECONNABORTED (C++11) | Connection aborted (macro constant) | 
| ECONNREFUSED (C++11) | Connection refused (macro constant) | 
| ECONNRESET (C++11) | Connection reset (macro constant) | 
| EDEADLK (C++11) | Resource deadlock would occur (macro constant) | 
| EDESTADDRREQ (C++11) | Destination address required (macro constant) | 
| EDOM | Mathematics argument out of domain of function (macro constant) | 
| EEXIST (C++11) | File exists (macro constant) | 
| EFAULT (C++11) | Bad address (macro constant) | 
| EFBIG (C++11) | File too large (macro constant) | 
| EHOSTUNREACH (C++11) | Host is unreachable (macro constant) | 
| EIDRM (C++11) | Identifier removed (macro constant) | 
| EILSEQ (C++11) | Illegal byte sequence (macro constant) | 
| EINPROGRESS (C++11) | Operation in progress (macro constant) | 
| EINTR (C++11) | Interrupted function (macro constant) | 
| EINVAL (C++11) | Invalid argument (macro constant) | 
| EIO (C++11) | I/O error (macro constant) | 
| EISCONN (C++11) | Socket is connected (macro constant) | 
| EISDIR (C++11) | Is a directory (macro constant) | 
| ELOOP (C++11) | Too many levels of symbolic links (macro constant) | 
| EMFILE (C++11) | File descriptor value too large (macro constant) | 
| EMLINK (C++11) | Too many links (macro constant) | 
| EMSGSIZE (C++11) | Message too large (macro constant) | 
| ENAMETOOLONG (C++11) | Filename too long (macro constant) | 
| ENETDOWN (C++11) | Network is down (macro constant) | 
| ENETRESET (C++11) | Connection aborted by network (macro constant) | 
| ENETUNREACH (C++11) | Network unreachable (macro constant) | 
| ENFILE (C++11) | Too many files open in system (macro constant) | 
| ENOBUFS (C++11) | No buffer space available (macro constant) | 
| ENODATA (C++11) | No message is available on the STREAM head read queue (macro constant) | 
| ENODEV (C++11) | No such device (macro constant) | 
| ENOENT (C++11) | No such file or directory (macro constant) | 
| ENOEXEC (C++11) | Executable file format error (macro constant) | 
| ENOLCK (C++11) | No locks available (macro constant) | 
| ENOLINK (C++11) | Link has been severed (macro constant) | 
| ENOMEM (C++11) | Not enough space (macro constant) | 
| ENOMSG (C++11) | No message of the desired type (macro constant) | 
| ENOPROTOOPT (C++11) | Protocol not available (macro constant) | 
| ENOSPC (C++11) | No space left on device (macro constant) | 
| ENOSR (C++11) | No STREAM resources (macro constant) | 
| ENOSTR (C++11) | Not a STREAM (macro constant) | 
| ENOSYS (C++11) | Function not supported (macro constant) | 
| ENOTCONN (C++11) | The socket is not connected (macro constant) | 
| ENOTDIR (C++11) | Not a directory (macro constant) | 
| ENOTEMPTY (C++11) | Directory not empty (macro constant) | 
| ENOTRECOVERABLE (C++11) | State not recoverable (macro constant) | 
| ENOTSOCK (C++11) | Not a socket (macro constant) | 
| ENOTSUP (C++11) | Not supported (macro constant) | 
| ENOTTY (C++11) | Inappropriate I/O control operation (macro constant) | 
| ENXIO (C++11) | No such device or address (macro constant) | 
| EOPNOTSUPP (C++11) | Operation not supported on socket (macro constant) | 
| EOVERFLOW (C++11) | Value too large to be stored in data type (macro constant) | 
| EOWNERDEAD (C++11) | Previous owner died (macro constant) | 
| EPERM (C++11) | Operation not permitted (macro constant) | 
| EPIPE (C++11) | Broken pipe (macro constant) | 
| EPROTO (C++11) | Protocol error (macro constant) | 
| EPROTONOSUPPORT (C++11) | Protocol not supported (macro constant) | 
| EPROTOTYPE (C++11) | Protocol wrong type for socket (macro constant) | 
| ERANGE | Result too large (macro constant) | 
| EROFS (C++11) | Read-only file system (macro constant) | 
| ESPIPE (C++11) | Invalid seek (macro constant) | 
| ESRCH (C++11) | No such process (macro constant) | 
| ETIME (C++11) | Stream ioctl() timeout (macro constant) | 
| ETIMEDOUT (C++11) | Connection timed out (macro constant) | 
| ETXTBSY (C++11) | Text file busy (macro constant) | 
| EWOULDBLOCK (C++11) | Operation would block (macro constant) | 
| EXDEV (C++11) | Cross-device link (macro constant) | 
[edit] Notes
Although the header <cerrno> is based on the C standard library header errno.h, the majority of the macros defined by <cerrno> were adopted by C++ from the POSIX standard, rather than the C standard library.


