Content-type: text/html Manpage of TCBsendto

TCBsendto

Section: Timely Computing Base (1)
Updated: 30 September 2002
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NAME

TCBsendto - sends a message from a TCB socket

 

SYNOPSIS

#include "tcb/tcb.h"

int TCBsendto(void* buff, int nbytes, unsigned int flags, struct sockaddr *to, int addrlen, TCBsocketDesc* desc, TCBtimestamp send_evt);  

DESCRIPTION

TCBsendto is used to transmit a message to another socket.

The address of the target is given by to with addrlen specifying its size. The length of the message is given by nbytes. If the message is too long to pass atomically through the underlying protocol, the error EMSGSIZE is returned, and the message is not transmitted.

No indication of failure to deliver is implicit in a TCBsendto. Locally detected errors are indicated by a return value of -1.

When the message does not fit into the send buffer of the socket, TCBsendto normally blocks, unless the socket has been placed in non-blocking I/O mode. In non-blocking mode it would return EAGAIN in this case. The select(2) call may be used to determine when it is possible to send more data. The parameter desc is the descriptor of the TCB socket. send_evt is the timestamp that signals the start of the interval that will be measured.

The flags parameter is a flagword and can contain the following flags:

MSG_DONTROUTE
Dont't use a gateway to send out the packet, only send to hosts on directly connected networks. This is usually used only by diagnostic or routing programs. This is only defined for protocol families that route; packet sockets don't.
MSG_DONTWAIT
Enables non-blocking operation; if the operation would block, EAGAIN is returned (this can also be enabled using the O_NONBLOCK with the F_SETFL fcntl(2)).
MSG_NOSIGNAL
Requests not to send SIGPIPE on errors on stream oriented sockets when the other end breaks the connection. The EPIPE error is still returned.

 

RETURN VALUES

The calls return the number of characters sent, or -1 if an error occurred.  

ERRORS

These are some standard errors generated by the socket layer. Additional errors may be generated and returned from the underlying protocol modules; see their respective manual pages.
EBADF
An invalid descriptor was specified.
ENOTSOCK
The argument s is not a socket.
EFAULT
An invalid user space address was specified for a parameter.
EMSGSIZE
The socket requires that message be sent atomically, and the size of the message to be sent made this impossible.
EAGAIN or EWOULDBLOCK
The socket is marked non-blocking and the requested operation would block.
ENOBUFS
The output queue for a network interface was full. This generally indicates that the interface has stopped sending, but may be caused by transient congestion. (This cannot occur in Linux, packets are just silently dropped when a device queue overflows.)
EINTR
A signal occurred.
ENOMEM
No memory available.
EINVAL
Invalid argument passed.
EPIPE
The local end has been shut down on a connection oriented socket. In this case the process will also receive a SIGPIPE unless MSG_NOSIGNAL is set.

 

SEE ALSO

sendto (2), TCBsocket, TCBbind (1), TCBwinfoport (1), TCBrecvfrom (1), TCBsocketClose (1)


 

Index

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUES
ERRORS
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 23:05:27 GMT, August 06, 2003