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Manual Reference Pages  - <errno.h> (P)

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errno.h - system error numbers

CONTENTS

Synopsis
Description
Application Usage
Rationale
Future Directions
See Also
Copyright

#include <errno.h>

Some of the functionality described on this reference page extends the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of IEEE Std 1003.1-2001 defers to the ISO C standard.

The ISO C standard only requires the symbols [EDOM], [EILSEQ], and [ERANGE] to be defined.

The <errno.h> header shall provide a declaration for errno and give positive values for the following symbolic constants. Their values shall be unique except as noted below.

E2BIG	Argument list too long.
EACCES	Permission denied.
EADDRINUSE
	Address in use.
EADDRNOTAVAIL
	Address not available.
EAFNOSUPPORT
	Address family not supported.
EAGAIN	Resource unavailable, try again (may be the same value as [EWOULDBLOCK]).
EALREADY
	Connection already in progress.
EBADF	Bad file descriptor.
EBADMSG	Bad message.
EBUSY	Device or resource busy.
ECANCELED
	Operation canceled.
ECHILD	No child processes.
ECONNABORTED
	Connection aborted.
ECONNREFUSED
	Connection refused.
ECONNRESET
	Connection reset.
EDEADLK	Resource deadlock would occur.
EDESTADDRREQ
	Destination address required.
EDOM	Mathematics argument out of domain of function.
EDQUOT	Reserved.
EEXIST	File exists.
EFAULT	Bad address.
EFBIG	File too large.
EHOSTUNREACH
	Host is unreachable.
EIDRM	Identifier removed.
EILSEQ	Illegal byte sequence.
EINPROGRESS
	Operation in progress.
EINTR	Interrupted function.
EINVAL	Invalid argument.
EIO	I/O error.
EISCONN	Socket is connected.
EISDIR	Is a directory.
ELOOP	Too many levels of symbolic links.
EMFILE	Too many open files.
EMLINK	Too many links.
EMSGSIZE
	Message too large.
EMULTIHOP
	Reserved.
ENAMETOOLONG
	Filename too long.
ENETDOWN
	Network is down.
ENETRESET
	Connection aborted by network.
ENETUNREACH
	Network unreachable.
ENFILE	Too many files open in system.
ENOBUFS	No buffer space available.
ENODATA	No message is available on the STREAM head read queue.
ENODEV	No such device.
ENOENT	No such file or directory.
ENOEXEC	Executable file format error.
ENOLCK	No locks available.
ENOLINK	Reserved.
ENOMEM	Not enough space.
ENOMSG	No message of the desired type.
ENOPROTOOPT
	Protocol not available.
ENOSPC	No space left on device.
ENOSR	No STREAM resources.
ENOSTR	Not a STREAM.
ENOSYS	Function not supported.
ENOTCONN
	The socket is not connected.
ENOTDIR	Not a directory.
ENOTEMPTY
	Directory not empty.
ENOTSOCK
	Not a socket.
ENOTSUP	Not supported.
ENOTTY	Inappropriate I/O control operation.
ENXIO	No such device or address.
EOPNOTSUPP
	Operation not supported on socket.
EOVERFLOW
	Value too large to be stored in data type.
EPERM	Operation not permitted.
EPIPE	Broken pipe.
EPROTO	Protocol error.
EPROTONOSUPPORT
	Protocol not supported.
EPROTOTYPE
	Protocol wrong type for socket.
ERANGE	Result too large.
EROFS	Read-only file system.
ESPIPE	Invalid seek.
ESRCH	No such process.
ESTALE	Reserved.
ETIME	Stream ioctl() timeout.
ETIMEDOUT
	Connection timed out.
ETXTBSY	Text file busy.
EWOULDBLOCK
	Operation would block (may be the same value as [EAGAIN]).
EXDEV	Cross-device link.

The following sections are informative.

Additional error numbers may be defined on conforming systems; see the System Interfaces volume of IEEE Std 1003.1-2001.

None.

None.

The System Interfaces volume of IEEE Std 1003.1-2001, Section 2.3, Error Numbers

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .