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Linux Error Eagain


errno is defined by the ISO C standard to be a modifiable lvalue of type int, and must not be explicitly declared; errno may be a macro. Some of these error codes can’t occur on GNU systems, but they can occur using the GNU C Library on other systems. POSIX.1-2001 only describes the MSG_OOB, MSG_PEEK, and MSG_WAITALL flags. MSG_DONTWAIT (since Linux 2.2) Enables nonblocking operation; if the operation would block, EAGAIN or EWOULDBLOCK is returned (this can also be enabled using the O_NONBLOCK flag with the F_SETFL fcntl(2)). this contact form

Macro: int EISDIR File is a directory; you cannot open a directory for writing, or create or remove hard links to it. The select(2) or poll(2) call may be used to determine when more data arrives. Macro: int EAFNOSUPPORT The address family specified for a socket is not supported; it is inconsistent with the protocol being used on the socket. It just means that there was nothing for that recvmsg() to receive just then.

Linux Errno Example

Macro: int EREMOTE An attempt was made to NFS-mount a remote file system with a file name that already specifies an NFS-mounted file. (This is an error on some operating systems, ENOTSOCK The argument sockfd is not a socket. The error is passed in an ancillary message with a type dependent on the protocol (for IPv4 IP_RECVERR). Thus, a subsequent receive call will return the same data.

asked 6 years ago viewed 5580 times active 6 years ago Blog How Do Software Developers in New York, San Francisco, London and Bangalore… Linked 0 BlockingIOError when send to non-blocking In GNU, this error is always synonymous with ENOMEM; you may get one or the other from network operations. Also, the following call send(sockfd, buf, len, flags); is equivalent to sendto(sockfd, buf, len, flags, NULL, 0); The argument sockfd is the file descriptor of the sending socket. Errno.h In C EOPNOTSUPP Some bit in the flags argument is inappropriate for the socket type.

Macro: int ECONNABORTED A network connection was aborted locally. Portability Note: In many older Unix systems, this condition was indicated by EWOULDBLOCK, which was a distinct error code different from EAGAIN. The Single UNIX Specification agrees, except that it has return values of type ssize_t (while 4.x BSD and libc4 and libc5 all have int). https://www.gnu.org/software/libc/manual/html_node/Error-Codes.html The recv() call is normally used only on a connected socket (see connect(2)) and is identical to recvfrom() with a NULL src_addr argument.

Some socket functions don’t make sense for all types of sockets, and others may not be implemented for all communications protocols. Errno.h Windows Macro: int ENOTSUP Not supported. MSG_DONTWAIT (since Linux 2.2) Enables nonblocking operation; if the operation would block, the call fails with the error EAGAIN or EWOULDBLOCK (this can also be enabled using the O_NONBLOCK flag with With a zero flags argument, send() is equivalent to write(2).

Posix Error Codes

Macro: int ENOTEMPTY Directory not empty, where an empty directory was expected. http://www.unix.com/ip-networking/147090-getting-eagain-error-while-sending.html Macro: int EIO Input/output error; usually used for physical read or write errors. Linux Errno Example Macro: int ENOEXEC Invalid executable file format. Errno.h Linux Kernel Is the equation pH+pOH=14 still valid at a different temperature?

Macro: int EUSERS The file quota system is confused because there are too many users. weblink See arp(7) for details. share|improve this answer answered Oct 21 '10 at 17:02 Eric Towers 3,268814 add a comment| up vote 2 down vote EAGAIN is usually returned when there is no outbound buffer space So the EAGAIN error isn't really telling you anything here. Linux Errno To String

Macro: int EPROCUNAVAIL ??? Additional errors may be generated and returned from the underlying protocol modules; see their manual pages. See Asynchronous I/O. http://globalinfoindex.com/linux-errno/linux-error-2.php See Socket Addresses.

Macro: int EADDRNOTAVAIL The requested socket address is not available; for example, you tried to give a socket a name that doesn’t match the local host name. Ebadf These function calls appeared in 4.2BSD. Macro: int EADDRINUSE The requested socket address is already in use.

Macro: int EBADF Bad file descriptor; for example, I/O on a descriptor that has been closed or reading from a descriptor open only for writing (or vice versa).

Macro: int EPROTOTYPE The socket type does not support the requested communications protocol. Macro: int EINPROGRESS An operation that cannot complete immediately was initiated on an object that has non-blocking mode selected. Macro: int EEXIST File exists; an existing file was specified in a context where it only makes sense to specify a new file. Errno 0 When src_addr is NULL, nothing is filled in; in this case, addrlen is not used, and should also be NULL.

Either you can have the read wait until some data arrives (blocking mode), or you can have it return immediately with an error (nonblocking mode). Macro: int EOPNOTSUPP The operation you requested is not supported. Not implemented for UNIX domain (unix(7)) sockets. his comment is here Macro: int EPFNOSUPPORT The socket communications protocol family you requested is not supported.

If a message is too long to fit in the supplied buffer, excess bytes may be discarded depending on the type of socket the message is received from. How to proceed in light of peer-review confidentiality? EINVAL Invalid argument passed. To make your program portable, you should check for both codes and treat them the same.

Thus, your program will never actually see EPIPE unless it has handled or blocked SIGPIPE. Macro: int EDOM Domain error; used by mathematical functions when an argument value does not fall into the domain over which the function is defined. Macro: int ENOTDIR A file that isn’t a directory was specified when a directory is required. Errors These are some standard errors generated by the socket layer.

secondly i m not sure but probably check buff size like below if is already predefined Code: getconf -a |grep SOCK_MAXBUF and set and get send/rec buff size maybe try like See Socket Addresses. Offline Quote #3 2005-12-14 09:37 PM i3839 Oddministrator From: Amsterdam Registered: 2003-06-07 Posts: 2,230 Re: Strategy for EAGAIN on non-blocking sockets An alternative would be to temporary set the socket to If yes then after how much time should I try again.

Note that any number of linked channels count as just one file opening; see Linked Channels. Macro: int EACCES Permission denied; the file permissions do not allow the attempted operation. POSIX.1-2001 allows either error to be returned for this case, and does not require these constants to have the same value, so a portable application should check for both possibilities. Macro: int ERPCMISMATCH ???

Macro: int ERANGE Range error; used by mathematical functions when the result value is not representable because of overflow or underflow.