man3type/iovec.3type

   1 .\" Copyright (c) 2022 by Alejandro Colomar <alx@kernel.org>
   2 .\"
   3 .\" SPDX-License-Identifier: Linux-man-pages-copyleft
   4 .\"
   5 .\"
   6 .TH iovec 3type (date) "Linux man-pages (unreleased)"
   7 .SH NAME
   8 iovec \- Vector I/O data structure
   9 .SH LIBRARY
  10 Standard C library
  11 .RI ( libc )
  12 .SH SYNOPSIS
  13 .EX
  14 .B #include <sys/uio.h>
  15 .PP
  16 .B struct iovec {
  17 .BR "    void   *iov_base;" "  /* Starting address */"
  18 .BR "    size_t  iov_len;" "   /* Size of the memory pointed to by "\c
  19 .IR iov_base ". */"
  20 .B };
  21 .EE
  22 .SH DESCRIPTION
  23 Describes a region of memory, beginning at
  24 .I iov_base
  25 address and with the size of
  26 .I iov_len
  27 bytes.
  28 System calls use arrays of this structure,
  29 where each element of the array represents a memory region,
  30 and the whole array represents a vector of memory regions.
  31 The maximum number of
  32 .I iovec
  33 structures in that array
  34 is limited by
  35 .B IOV_MAX
  36 (defined in
  37 .IR <limits.h> ,
  38 or accessible via the call
  39 .IR sysconf(_SC_IOV_MAX) ).
  40 .SH STANDARDS
  41 POSIX.1-2001 and later.
  42 .SH NOTES
  43 The following header also provides this type:
  44 .IR <sys/socket.h> .
  45 .SH SEE ALSO
  46 .BR process_madvise (2),
  47 .BR readv (2)