Someone here (I think it was Justin?) was curious to see the man page for
solaris's new sendfilev() implementation. Sun just released it in patch
108808-30, and here it is below:
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 containing the length of the buffer.
PARAMETERS
The sendfilev() function supports the following parameters:
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Extended Library Functions sendfilev(3EXT)
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 send-
filevec 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.
ENOMEM
Out of memory.
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.
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Extended Library Functions sendfilev(3EXT)
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
This error code indicates one of the following:
o Mandatory file or record locking is set.
o O_NDELAY or O-NONBLOCK is set, and there is a
blocking record lock.
o An attempt has been made to write to a stream
that cannot accept data with the O_NDELAY or O-
NONBLOCK flag set.
o A write to a pipe of FIFO of PIP_BUF bytes or
less is requested and less than nbytes of free
space is available.
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 con-
nected state, that is, socket(), accept(), and bind() opera-
tion are complete.
#include <sys/sendfile.h>
.
.
.
int
main (int argc, char eargv[]){
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;
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Extended Library Functions sendfilev(3EXT)
vec[1].sfv_len = 100;
ret = sendfilev(sockfd, vec, 2, &xfer);
.
.
.
}
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:
____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Availability | SUNWcsl(32 -bit) |
|_____________________________|_____________________________|
| | SUNWcslx (64-bit) |
|_____________________________|_____________________________|
| Interface Stability | Evolving |
|_____________________________|_____________________________|
| MT-Level | MT-Safe |
|_____________________________|_____________________________|
SEE ALSO
open(2), writev(2), attributes(5)
