sendfilev(3EXT) 					    Extended Library Functions						   sendfilev(3EXT)

NAME

       sendfilev - send a file

SYNOPSIS

       cc [ flag... ] file... -lsendfile  [ library... ]
       #include <sys/sendfile.h>

       ssize_t sendfilev(int fildes, const struct sendfilevec *vec, int sfvcnt, size_t *xferred);

DESCRIPTION

       The  sendfilev()  function  attempts  to  write	data  from the sfvcnt buffers specified by the members of vec array: vec[0], vec[1], ... ,
       vec[sfvcnt-1]. fildes is a file descriptor to a regular file or to a AF_NCA, AF_INET, or AF_INET6 family type SOCK_STREAM  socket  that	is
       open for writing.

       This function is analogous to the writev() system call. See writev(2). However, instead of sending out chunks of data, sendfilev() can read
       input data from data buffers or file descriptors.

       The following is the sendfilevec structure:

       typedef struct sendfilevec {
	       int     sfv_fd;	       /* input fd */
	       uint_t  sfv_flag;       /* Flags. see below */
	       off_t   sfv_off;        /* offset to start reading from */
	       size_t  sfv_len;        /* amount of data */
       } sendfilevec_t;

       #define SFV_FD_SELF     (-2)

       To send a file, open the file for reading. Point sfv_fd to the file descriptor returned as a result. See open(2).  sfv_off  should  contain
       the offset within the file. sfv_len should have the length of the file to be transferred.

       The xferred parameter is updated to record the total number  of bytes written to out_fd.

       The sfv_flag field is reserved and should be set to zero.

       To send data directly from the address space of the process, set sfv_fd to SFV_FD_SELF. sfv_off should point to the data, with sfv_len con-
       taining the length of the buffer.

PARAMETERS

       The sendfilev() function supports the following parameters:

       fildes	       A file descriptor to a regular file or to a AF_NCA, AF_INET, or AF_INET6 family type SOCK_STREAM socket that  is  open  for
		       writing. For AF_NCA, the protocol type should be zero.

       vec	       An array of SENDFILEVEC_T, as defined in the sendfilevec structure above.

       sfvcnt	       The number of members in vec.

       xferred	       The total number of bytes written to out_fd.

RETURN VALUES

       Upon  successful  completion, sendfilev() returns total number of bytes written to out_fd. Otherwise,  it  returns  -1, and errno is set to
       indicate an error.  xferred contains the amount of data successfuly transferred, which can be used to discover the error vector.

ERRORS

       EAFNOSUPPORT	       The implementation does not support the			       specified address family for socket.

       EPROTOTYPE	       The socket type is not supported.

       EBADF		       The fildes argument is not a valid descriptor			     open for writing or an sfv_fd is  invalid	or
			       not open for reading.

       EACCES		       The  process  does not have appropriate privileges or one of the files pointed by sfv_fd does not  have appropriate
			       permissions.

       EPIPE		       The fildes argument is a socket that has been			     shut  down  for  writing.

       EIO		       An I/O error occurred while accessing the file system.

       EFAULT		       The vec argument points to an illegal address.

       EFAULT		       The xferred argument points to an illegal address.

       EINVAL		       The sfvcnt argument was less than or  equal  to	0. One of the sfv_len in vec array was less than or equal to 0, or
			       greater than the file size. An sfv_fd is not seekable.

       EAGAIN		       Mandatory  file	or  record  locking is set on either the file descriptor or output file descriptor if it points at
			       regular files. O_NDELAY or O_NONBLOCK is  set, and there is a blocking record lock.  An attempt has  been  made	to
			       write to a stream that cannot accept data with the O_NDELAY or the O_NONBLOCK flag set.

USAGE

       The sendfilev() function has a transitional interface for 64-bit file offsets. See lf64(5).

EXAMPLES

       The  following  example	sends 2 vectors, one of HEADER data and a file of length 100 over sockfd. sockfd is in a connected state, that is,
       socket(), accept(), and bind() operation are complete.

       #include <sys/sendfile.h>
       .
       .
       .
       int
       main (int argc, char *argv[]){
	 int sockfd;
	 ssize_t ret;
	 size_t xfer;
	 struct sendfilevec vec[2];
	   .
	   .
	   .
	 vec[0].sfv_fd = SFV_FD_SELF;
	 vec[0].sfv_flag = 0;
	 vec[0].sfv_off = "HEADER_DATA";
	 vec[0].sfv_len = strlen("HEADER_DATA");
	 vec[1].sfv_fd = open("input_file",.... );
	 vec[1].sfv_flag = 0;
	 vec[1].sfv_off = 0;
	 vec[1].sfv_len = 100;

	 ret = sendfilev(sockfd, vec, 2, &xfer);
       .
       .
       .
       }

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Evolving			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       open(2), writev(2), libsendfile(3LIB), sendfile(3EXT), socket(3SOCKET), attributes(5)

SunOS 5.10							    19 Apr 2004 						   sendfilev(3EXT)