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Annotation of cci/usr/src/man/man2/send.2, revision 1.1.1.1

1.1       root        1: .TH SEND 2 "20 September 1983"
                      2: .UC 4
                      3: .SH NAME
                      4: send, sendto, sendmsg \- send a message from a socket
                      5: .SH SYNOPSIS
                      6: .nf
                      7: .ft B
                      8: #include <sys/types.h>
                      9: #include <sys/socket.h>
                     10: .PP
                     11: .ft B
                     12: cc = send(s, msg, len, flags)
                     13: int cc, s;
                     14: char *msg;
                     15: int len, flags;
                     16: .PP
                     17: .ft B
                     18: cc = sendto(s, msg, len, flags, to, tolen)
                     19: int cc, s;
                     20: char *msg;
                     21: int len, flags;
                     22: struct sockaddr *to;
                     23: int tolen;
                     24: .PP
                     25: .ft B
                     26: cc = sendmsg(s, msg, flags)
                     27: int cc, s;
                     28: struct msghdr msg[];
                     29: int flags;
                     30: .fi
                     31: .SH DESCRIPTION
                     32: .IR Send ,
                     33: .IR sendto ,
                     34: and
                     35: .I sendmsg
                     36: are used to transmit a message to another socket.
                     37: .I Send
                     38: may be used only when the socket is in a 
                     39: .I connected
                     40: state, while 
                     41: .I sendto
                     42: and
                     43: .I sendmsg
                     44: may be used at any time.
                     45: .PP
                     46: The address of the target is given by
                     47: .I to
                     48: with 
                     49: .I tolen
                     50: specifying its size.
                     51: The length of the message is given by
                     52: .IR len .
                     53: If the message is too long to pass atomically through the
                     54: underlying protocol, then the error EMSGSIZE is returned, and
                     55: the message is not transmitted.
                     56: .PP
                     57: No indication of failure to deliver is implicit in a
                     58: .IR send .
                     59: Return values of \-1 indicate some locally detected errors.
                     60: .PP
                     61: If no messages space is available at the socket to hold
                     62: the message to be transmitted, then
                     63: .I send
                     64: normally blocks, unless the socket has been placed in
                     65: non-blocking i/o mode.
                     66: The
                     67: .IR select (2)
                     68: call may be used to determine when it is possible to
                     69: send more data.
                     70: .PP
                     71: The
                     72: .I flags
                     73: parameter may be set to MSG_OOB to send \*(lqout-of-band\*(rq
                     74: data on sockets which support this notion (e.g. SOCK_STREAM).
                     75: .PP
                     76: See 
                     77: .IR recv (2)
                     78: for a description of the
                     79: .I msghdr
                     80: structure, of sending and receiving file descriptors in Unix domain via this
                     81: .I msghdr
                     82: structure, and of receiving out-of-band data.
                     83: .SH "RETURN VALUE
                     84: The call returns the number of characters sent, or \-1
                     85: if an error occurred.
                     86: .SH "ERRORS
                     87: .TP 20
                     88: [EBADF]
                     89: An invalid descriptor was specified.
                     90: .TP 20
                     91: [ENOTSOCK]
                     92: The argument \fIs\fP is not a socket.
                     93: .TP 20
                     94: [EFAULT]
                     95: An invalid user space address was specified for a parameter.
                     96: .TP 20
                     97: [EMSGSIZE]
                     98: The socket requires that message be sent atomically,
                     99: and the size of the message to be sent made this impossible.
                    100: .TP 20
                    101: [EWOULDBLOCK]
                    102: The socket is marked non-blocking and the requested operation
                    103: would block.
                    104: .SH SEE ALSO
                    105: recv(2), socket(2). See also bind(2) for address formats in different
                    106: communication domains.
                    107: .SH BUGS
                    108: Out-of-band data is only 1 character long.

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