Copyright (c) 2009, Sun Microsystems, Inc. All Rights Reserved.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
Copyright 2022 Garrett D'Amore
cc [ flag.\|.\|. ] file.\|.\|. -lsendfile [ library... ] #include <sys/sendfile.h> ssize_t sendfilev(int fildes, const struct sendfilevec *vec, int sfvcnt, size_t *xferred);
A file descriptor to a regular file or to a AF_INET or AF_INET6 family type SOCK_STREAM socket that is open for writing.
An array of SENDFILEVEC_T, as defined in the sendfilevec structure below.
The number of members in vec.
The total number of bytes written to out_fd.
This function is analogous to writev(2), but can read from both buffers and file descriptors. Unlike writev(), in the case of multiple writers to a file the effect of sendfilev() is not necessarily atomic; the writes may be interleaved. Application-specific synchronization methods must be employed if this causes problems.
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 and 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 argument 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.
The process does not have appropriate privileges or one of the files pointed by sfv_fd does not have appropriate permissions.
The implementation does not support the specified address family for socket.
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.
The fildes argument is not a valid descriptor open for writing or an sfv_fd is invalid or not open for reading.
The vec argument points to an illegal address. The xferred argument points to an illegal address.
A signal was caught during the write operation and no data was transferred.
The sfvcnt argument was less than or equal to 0. One of the sfv_len values in vec array was less than or equal to 0, or greater than the file size. An sfv_fd is not seekable. Fewer bytes were transferred than were requested.
An I/O error occurred while accessing the file system.
The fildes argument is a socket that has been shut down for writing. The SIGPIPE signal is generated to the calling thread. The process dies unless special provisions were taken to catch or ignore the signal.
The socket type is not supported.
#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); . . . }
ATTRIBUTE TYPE ATTRIBUTE VALUE |
Interface Stability Committed |
MT-Level MT-Safe |