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) 
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   Permission denied  (macro constant)  | 
|    EADDRINUSE 
(C++11) 
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   Address in use  (macro constant)  | 
|    EADDRNOTAVAIL 
(C++11) 
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   Address not available  (macro constant)  | 
|    EAFNOSUPPORT 
(C++11) 
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   Address family not supported  (macro constant)  | 
|    EAGAIN 
(C++11) 
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   Resource unavailable, try again  (macro constant)  | 
|    EALREADY 
(C++11) 
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   Connection already in progress  (macro constant)  | 
|    EBADF 
(C++11) 
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   Bad file descriptor  (macro constant)  | 
|    EBADMSG 
(C++11) 
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   Bad message  (macro constant)  | 
|    EBUSY 
(C++11) 
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   Device or resource busy  (macro constant)  | 
|    ECANCELED 
(C++11) 
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   Operation canceled  (macro constant)  | 
|    ECHILD 
(C++11) 
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   No child processes  (macro constant)  | 
|    ECONNABORTED 
(C++11) 
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   Connection aborted  (macro constant)  | 
|    ECONNREFUSED 
(C++11) 
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   Connection refused  (macro constant)  | 
|    ECONNRESET 
(C++11) 
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   Connection reset  (macro constant)  | 
|    EDEADLK 
(C++11) 
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   Resource deadlock would occur  (macro constant)  | 
|    EDESTADDRREQ 
(C++11) 
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   Destination address required  (macro constant)  | 
|    EDOM  | 
   Mathematics argument out of domain of function  (macro constant)  | 
|    EEXIST 
(C++11) 
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   File exists  (macro constant)  | 
|    EFAULT 
(C++11) 
 | 
   Bad address  (macro constant)  | 
|    EFBIG 
(C++11) 
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   File too large  (macro constant)  | 
|    EHOSTUNREACH 
(C++11) 
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   Host is unreachable  (macro constant)  | 
|    EIDRM 
(C++11) 
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   Identifier removed  (macro constant)  | 
|    EILSEQ 
(C++11) 
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   Illegal byte sequence  (macro constant)  | 
|    EINPROGRESS 
(C++11) 
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   Operation in progress  (macro constant)  | 
|    EINTR 
(C++11) 
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   Interrupted function  (macro constant)  | 
|    EINVAL 
(C++11) 
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   Invalid argument  (macro constant)  | 
|    EIO 
(C++11) 
 | 
   I/O error  (macro constant)  | 
|    EISCONN 
(C++11) 
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   Socket is connected  (macro constant)  | 
|    EISDIR 
(C++11) 
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   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) 
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   Too many links  (macro constant)  | 
|    EMSGSIZE 
(C++11) 
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   Message too large  (macro constant)  | 
|    ENAMETOOLONG 
(C++11) 
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   Filename too long  (macro constant)  | 
|    ENETDOWN 
(C++11) 
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   Network is down  (macro constant)  | 
|    ENETRESET 
(C++11) 
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   Connection aborted by network  (macro constant)  | 
|    ENETUNREACH 
(C++11) 
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   Network unreachable  (macro constant)  | 
|    ENFILE 
(C++11) 
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   Too many files open in system  (macro constant)  | 
|    ENOBUFS 
(C++11) 
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   No buffer space available  (macro constant)  | 
|    ENODATA 
(C++11) 
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   No message is available on the STREAM head read queue  (macro constant)  | 
|    ENODEV 
(C++11) 
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   No such device  (macro constant)  | 
|    ENOENT 
(C++11) 
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   No such file or directory  (macro constant)  | 
|    ENOEXEC 
(C++11) 
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   Executable file format error  (macro constant)  | 
|    ENOLCK 
(C++11) 
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   No locks available  (macro constant)  | 
|    ENOLINK 
(C++11) 
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   Link has been severed  (macro constant)  | 
|    ENOMEM 
(C++11) 
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   Not enough space  (macro constant)  | 
|    ENOMSG 
(C++11) 
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   No message of the desired type  (macro constant)  | 
|    ENOPROTOOPT 
(C++11) 
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   Protocol not available  (macro constant)  | 
|    ENOSPC 
(C++11) 
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   No space left on device  (macro constant)  | 
|    ENOSR 
(C++11) 
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   No STREAM resources  (macro constant)  | 
|    ENOSTR 
(C++11) 
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   Not a STREAM  (macro constant)  | 
|    ENOSYS 
(C++11) 
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   Function not supported  (macro constant)  | 
|    ENOTCONN 
(C++11) 
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   The socket is not connected  (macro constant)  | 
|    ENOTDIR 
(C++11) 
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   Not a directory  (macro constant)  | 
|    ENOTEMPTY 
(C++11) 
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   Directory not empty  (macro constant)  | 
|    ENOTRECOVERABLE 
(C++11) 
 | 
   State not recoverable  (macro constant)  | 
|    ENOTSOCK 
(C++11) 
 | 
   Not a socket  (macro constant)  | 
|    ENOTSUP 
(C++11) 
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   Not supported  (macro constant)  | 
|    ENOTTY 
(C++11) 
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   Inappropriate I/O control operation  (macro constant)  | 
|    ENXIO 
(C++11) 
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   No such device or address  (macro constant)  | 
|    EOPNOTSUPP 
(C++11) 
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   Operation not supported on socket  (macro constant)  | 
|    EOVERFLOW 
(C++11) 
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   Value too large to be stored in data type  (macro constant)  | 
|    EOWNERDEAD 
(C++11) 
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   Previous owner died  (macro constant)  | 
|    EPERM 
(C++11) 
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   Operation not permitted  (macro constant)  | 
|    EPIPE 
(C++11) 
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   Broken pipe  (macro constant)  | 
|    EPROTO 
(C++11) 
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   Protocol error  (macro constant)  | 
|    EPROTONOSUPPORT 
(C++11) 
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   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) 
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   Invalid seek  (macro constant)  | 
|    ESRCH 
(C++11) 
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   No such process  (macro constant)  | 
|    ETIME 
(C++11) 
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   Stream ioctl() timeout  (macro constant)  | 
|    ETIMEDOUT 
(C++11) 
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   Connection timed out  (macro constant)  | 
|    ETXTBSY 
(C++11) 
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   Text file busy  (macro constant)  | 
|    EWOULDBLOCK 
(C++11) 
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   Operation would block  (macro constant)  | 
|    EXDEV 
(C++11) 
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   Cross-device link  (macro constant)  |