887 lines
20 KiB
HTML
887 lines
20 KiB
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
|
|
<html>
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
|
<meta name="Copyright" content="Copyright (c) 2006 by IBM Corporation">
|
|
<title>writev()--Write to Descriptor Using Multiple Buffers</title>
|
|
<!-- All rights reserved. Licensed Materials Property of IBM -->
|
|
<!-- US Government Users Restricted Rights -->
|
|
<!-- Use, duplication or disclosure restricted by -->
|
|
<!-- GSA ADP Schedule Contract with IBM Corp. -->
|
|
<!-- Begin Header Records ========================================== -->
|
|
<!-- file cleaned -->
|
|
<!-- Unix2 SCRIPT J converted by B2H R4.1 (346) (CMS) by V2KEA304 -->
|
|
<!-- at RCHVMW2 on 17 Feb 1999 at 11:05:09 -->
|
|
<!-- Change History: -->
|
|
<!-- 010320 JTROUS Include Journal ERRNOs, should have in V5R1 -->
|
|
<!-- 010703 JTROUS ERESTART, EINTR,Add dev/zero, V5R2, DCR 98686 -->
|
|
<!-- 011022 JTROUS Changes from API Review 1, V5R2 -->
|
|
<!-- also add in info from PASE I0 for 98391 -->
|
|
<!-- 020618 EMIG: updated for NFS threadsafety, V5R3 -->
|
|
<!-- 020624 RTHEIS: Add fclear() and fclear64(), V5R3 -->
|
|
<!-- 0206?? JET This file has undergone html cleanup -->
|
|
<!-- 020718 MFENLON: updated for QFileSvr.400 threadsafety, V5R3 -->
|
|
<!-- 050407 JTROUS: fix enums, no change flag, V5R4 -->
|
|
<!-- End Header Records -->
|
|
<!-- Edited by Kersten Feb 02 -->
|
|
|
|
<link rel="stylesheet" type="text/css" href="../rzahg/ic.css">
|
|
</head>
|
|
<body>
|
|
|
|
<!-- Java sync-link -->
|
|
<script language="Javascript" src="../rzahg/synch.js" type="text/javascript">
|
|
</script>
|
|
|
|
<a name="Top_Of_Page"></a>
|
|
|
|
<h2>writev()--Write to Descriptor Using Multiple Buffers</h2>
|
|
|
|
<div class="box" style="width: 70%;">
|
|
<br>
|
|
Syntax<br>
|
|
<pre>
|
|
#include <sys/types.h>
|
|
#include <sys/uio.h>
|
|
|
|
int writev(int <em>descriptor</em>,
|
|
struct iovec *<em>io_vector</em>[],
|
|
int <em>vector_length</em>)
|
|
</pre>
|
|
|
|
<br>
|
|
Service Program Name: QP0LLIB1<br>
|
|
<!-- iddvc RMBR -->
|
|
<br>
|
|
Default Public Authority: *USE<br>
|
|
<!-- iddvc RMBR -->
|
|
<br>
|
|
Threadsafe: Conditional; see <a href="#USAGE_NOTES">Usage
|
|
Notes</a>.<br>
|
|
<!-- iddvc RMBR -->
|
|
<br>
|
|
</div>
|
|
|
|
|
|
|
|
<p>The <strong>writev()</strong> function is used to write data to a file or socket
|
|
descriptor. <strong>writev()</strong> provides a way for the data that is going to be
|
|
written to be stored in several different buffers (<em>scatter/gather
|
|
I/O</em>).</p>
|
|
|
|
<p><strong>Note:</strong> When the write completes successfully, the S_ISUID
|
|
(set-user-ID) and S_ISGID (set-group-ID) bits of the file mode will be cleared.
|
|
If the write is unsuccessful, the bits are undefined.</p>
|
|
|
|
<p>See <a href="write.htm">write()--Write to Descriptor</a> for more
|
|
information related to writing to a descriptor.</p>
|
|
|
|
<br>
|
|
<h3>Parameters</h3>
|
|
|
|
<dl>
|
|
<dt><strong>descriptor</strong></dt>
|
|
|
|
<dd>(Input) The descriptor to which the data is to be written. The descriptor
|
|
refers to either a file or a socket.<br>
|
|
<br>
|
|
</dd>
|
|
|
|
<dt><strong>io_vector</strong>[]</dt>
|
|
|
|
<dd>(Input) The pointer to an array of type <strong>struct iovec</strong>.
|
|
<strong>struct iovec</strong> contains a sequence of pointers to buffers in
|
|
which the data to be written is stored. The structure pointed to by the <em>
|
|
io_vector</em> parameter is defined in <strong><sys/uio.h></strong>.
|
|
|
|
<pre>
|
|
struct iovec {
|
|
void *iov_base;
|
|
size_t iov_len;
|
|
}
|
|
</pre>
|
|
|
|
<p><em>iov_base</em> and <em>iov_len</em> are the only fields in <em>iovec</em>
|
|
used by sockets. <em>iov_base</em> contains the pointer to a buffer and <em>
|
|
iov_len</em> contains the buffer length. The rest of the fields are
|
|
reserved.</p>
|
|
</dd>
|
|
|
|
<dt><strong>vector_length</strong></dt>
|
|
|
|
<dd>(Input) The number of entries in <em>io_vector</em>.</dd>
|
|
</dl>
|
|
|
|
<br>
|
|
<h3>Authorities</h3>
|
|
|
|
<p>No authorization is required.</p>
|
|
|
|
<br>
|
|
<h3>Return Value</h3>
|
|
|
|
<table cellpadding="5">
|
|
<!-- cols="10 90" -->
|
|
<tr>
|
|
<td align="left" valign="top"><em>value</em></td>
|
|
<td align="left" valign="top"><strong>writev()</strong> was successful. The
|
|
value returned is the number of bytes actually written.
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top"><em>-1</em></td>
|
|
<td align="left" valign="top"><strong>writev()</strong> was not successful. The
|
|
<em>errno</em> global variable is set to indicate the error.</td>
|
|
</tr>
|
|
</table>
|
|
|
|
<br>
|
|
<h3>Error Conditions</h3>
|
|
|
|
<p>If <strong>writev()</strong> is not successful, <em>errno</em> usually
|
|
indicates one of the following errors. Under some conditions, <em>errno</em>
|
|
could indicate an error other than those listed here.</p>
|
|
|
|
<table cellpadding="5">
|
|
<!-- cols="25 75" -->
|
|
|
|
<tr>
|
|
<th align="left" valign="bottom">Error condition</th>
|
|
<th align="left" valign="bottom">Additional information</th>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EACCES">EACCES</a>]</em></td>
|
|
|
|
|
|
<td align="left" valign="top">
|
|
<p>If you are accessing a remote file through the Network File System, update
|
|
operations to file permissions at the server are not reflected at the client
|
|
until updates to data that is stored locally by the Network File System take
|
|
place. (Several options on the Add Mounted File System (ADDMFS) command
|
|
determine the time between refresh operations of local data.) Access to a
|
|
remote file may also fail due to different mappings of user IDs (UID) or group
|
|
IDs (GID) on the local and remote systems.</p>
|
|
<p>If writing to a socket, this error code indicates one of the following:</p>
|
|
<ul>
|
|
<li>The destination address specified is a broadcast address and the socket
|
|
option <samp>SO_BROADCAST</samp> was not set (with a <em>
|
|
setsockopt()</em>).</li>
|
|
<li>The process does not have the appropriate privileges to the destination
|
|
address. This error code can only be returned on a socket with an address
|
|
family of <samp>AF_INET</samp> and a type of <samp>SOCK_DGRAM</samp>.</li>
|
|
</ul>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EAGAIN">EAGAIN</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EBADF">EBADF</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EBADFID">EBADFID</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EBUSY">EBUSY</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EDAMAGE">EDAMAGE</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EFAULT">EFAULT</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EFBIG">EFBIG</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>The size of the object would exceed the system allowed maximum size or the
|
|
process soft file size limit.
|
|
The file is a regular file, <em>nbyte</em> is greater than 0, and the
|
|
starting offset is greater than or equal to 2 GB minus 2 bytes.</p>
|
|
</td>
|
|
</tr>
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EINTR">EINTR</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EINVAL">EINVAL</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>For example, the file resides in a file system that does not support large files, and the
|
|
starting offset exceeds 2GB minus 2 bytes.</p>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EIO">EIO</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EJRNDAMAGE">EJRNDAMAGE</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EJRNENTTOOLONG">EJRNENTTOOLONG</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EJRNINACTIVE">EJRNINACTIVE</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EJRNRCVSPC">EJRNRCVSPC</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr><tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENEWJRN">ENEWJRN</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENEWJRNRCV">ENEWJRNRCV</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENOMEM">ENOMEM</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENOSPC">ENOSPC</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENOTAVAIL">ENOTAVAIL</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENOTSAFE">ENOTSAFE</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ERESTART">ERESTART</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ESTALE">ESTALE</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>If you are accessing a remote file through the Network File System, the file
|
|
may have been deleted at the server.</p>
|
|
</td>
|
|
</tr>
|
|
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ETRUNC">ETRUNC</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EUNKNOWN">EUNKNOWN</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
</table>
|
|
|
|
<p>When the descriptor refers to a socket, <em>errno</em> could indicate one of
|
|
the following errors:</p>
|
|
|
|
<table cellpadding="5">
|
|
<!-- cols="25 75" -->
|
|
|
|
<tr>
|
|
<th align="left" valign="bottom">Error condition</th>
|
|
<th align="left" valign="bottom">Additional information</th>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ECONNREFUSED">ECONNREFUSED</a>]</em></td>
|
|
|
|
<td>
|
|
<p>This error code can only be returned on sockets that use a connectionless
|
|
transport service.</p>
|
|
</td></tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EDESTADDRREQ">EDESTADDRREQ</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>A destination address has not been associated with the socket pointed to by
|
|
the <em>fildes</em> parameter. This error code can only be returned on sockets
|
|
that use a connectionless transport service.</p>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EHOSTDOWN">EHOSTDOWN</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>This error code can only be returned on sockets that use a connectionless
|
|
transport service.</p>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EHOSTUNREACH">EHOSTUNREACH</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>This error code can only be returned on sockets that use a connectionless
|
|
transport service.</p>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EINTR">EINTR</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EMSGSIZE">EMSGSIZE</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>The data to be sent could not be sent atomically because the size specified
|
|
by <em>nbyte</em> is too large.</p>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENETDOWN">ENETDOWN</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>This error code can only be returned on sockets that use a connectionless
|
|
transport service.</p>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENETUNREACH">ENETUNREACH</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>This error code can only be returned on sockets that use a connectionless
|
|
transport service.</p>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENOBUFS">ENOBUFS</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENOTCONN">ENOTCONN</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>This error code is returned only on sockets that use a connection-oriented
|
|
transport service.</p>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EPIPE">EPIPE</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EUNATCH">EUNATCH</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EWOULDBLOCK">EWOULDBLOCK</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
</table>
|
|
|
|
<p>If interaction with a file server is required to access the object, <em>
|
|
errno</em> could indicate one of the following errors:</p>
|
|
|
|
<table cellpadding="5">
|
|
<!-- cols="25 75" -->
|
|
|
|
<tr>
|
|
<th align="left" valign="bottom">Error condition</th>
|
|
<th align="left" valign="bottom">Additional information</th>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EADDRNOTAVAIL">EADDRNOTAVAIL</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ECONNABORTED">ECONNABORTED</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ECONNREFUSED">ECONNREFUSED</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ECONNRESET">ECONNRESET</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EHOSTDOWN">EHOSTDOWN</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EHOSTUNREACH">EHOSTUNREACH</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENETDOWN">ENETDOWN</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENETRESET">ENETRESET</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ENETUNREACH">ENETUNREACH</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ESTALE">ESTALE</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
<p>If you are accessing a remote file through the Network File System, the file
|
|
may have been deleted at the server.</p>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#ETIMEDOUT">ETIMEDOUT</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">
|
|
<em>[<a href="unix14.htm#EUNATCH">EUNATCH</a>]</em></td>
|
|
|
|
<td align="left" valign="top">
|
|
|
|
</td>
|
|
</tr>
|
|
</table>
|
|
|
|
<br>
|
|
<br>
|
|
<h3>Error Messages</h3>
|
|
|
|
<table width="100%" cellpadding="5">
|
|
<tr>
|
|
<th align="left" valign="top">Message ID</th>
|
|
<th align="left" valign="top">Error Message Text</th>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td width="15%" valign="top">CPE3418 E</td>
|
|
<td width="85%" valign="top">Possible APAR condition or hardware failure.</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">CPF3CF2 E</td>
|
|
<td align="left" valign="top">Error(s) occurred during running of &1
|
|
API.</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">CPF9872 E</td>
|
|
<td align="left" valign="top">Program or service program &1 in library
|
|
&2 ended. Reason code &3.</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">CPFA081 E</td>
|
|
<td align="left" valign="top">Unable to set return value or error code.</td>
|
|
</tr>
|
|
|
|
<tr>
|
|
<td align="left" valign="top">CPFA0D4 E</td>
|
|
<td align="left" valign="top">File system error occurred. Error number
|
|
&1.</td>
|
|
</tr>
|
|
</table>
|
|
|
|
<br>
|
|
<br>
|
|
<h3><a name="USAGE_NOTES">Usage Notes</a></h3>
|
|
|
|
<ol>
|
|
<li>This function will fail with error code [ENOTSAFE] when all the following
|
|
conditions are true:
|
|
|
|
<ul>
|
|
<li>Where multiple threads exist in the job.</li>
|
|
|
|
<li>The object on which this function is operating resides in a file system
|
|
that is not threadsafe. Only the following file systems are threadsafe for this
|
|
function:
|
|
|
|
<ul>
|
|
<li>"Root" (/)</li>
|
|
|
|
<li>QOpenSys</li>
|
|
|
|
<li>User-defined</li>
|
|
|
|
<li>QNTC</li>
|
|
|
|
<li>QSYS.LIB</li>
|
|
|
|
<li>Independent ASP QSYS.LIB</li>
|
|
|
|
<li>QOPT</li>
|
|
|
|
<li>Network File System</li>
|
|
|
|
<li>QFileSvr.400</li>
|
|
|
|
</ul>
|
|
</li>
|
|
</ul>
|
|
|
|
<br>
|
|
</li>
|
|
|
|
<li>
|
|
<p><strong>writev()</strong> only works with sockets on which a <em>connect()</em> has
|
|
been issued, since the call does not allow the caller to specify a destination
|
|
address.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<p><strong>writev()</strong> is an atomic operation on sockets of type <samp>
|
|
SOCK_DGRAM</samp> and <samp>SOCK_RAW</samp> in that it produces one packet of
|
|
data every time it is issued. For example, a <strong>writev()</strong> to a datagram
|
|
socket results in a single datagram.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<p>To broadcast on an <samp>AF_INET</samp> socket, the socket option <samp>
|
|
SO_BROADCAST</samp> must be set (with a <em>setsockopt()</em>).</p>
|
|
</li>
|
|
|
|
<li>When using a connection-oriented transport service, all errors except
|
|
<samp>[EUNATCH]</samp> and <samp>[EUNKNOWN]</samp> are mapped to <samp>
|
|
[EPIPE]</samp> on an output operation when either of the following occurs:
|
|
|
|
<ul>
|
|
<li>A connection that is in progress is unsuccessful.<br>
|
|
</li>
|
|
|
|
<li>An established connection is broken.</li>
|
|
</ul>
|
|
|
|
<br>
|
|
|
|
|
|
<p>To get the actual error, use <em>getsockopt()</em> with the <samp>
|
|
SO_ERROR</samp> option, or perform an input operation (for example, <em>
|
|
read()</em>).</p>
|
|
</li>
|
|
|
|
<li>
|
|
<p>For the file systems that do not support large files, <strong>
|
|
writev()</strong> will return [EINVAL] if the starting offset exceeds 2GB minus
|
|
2 bytes, regardless of how the file was opened. For the file systems that do
|
|
support large files, <strong>writev()</strong> will return [EFBIG] if the
|
|
starting offset exceeds 2GB minus 2 bytes and the file was not opened for large
|
|
file access.</p>
|
|
</li>
|
|
|
|
<li>QFileSvr.400 File System Differences
|
|
|
|
<p>The largest buffer size allowed is 16 megabytes. If a larger buffer is
|
|
passed, the error EINVAL will be received.</p>
|
|
</li>
|
|
|
|
<li>QOPT File System Differences
|
|
|
|
<p>When writing to files on volumes formatted in Universal Disk Format (UDF),
|
|
byte locks on the range being written are ignored.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<p>Using this function successfully on the dev/null or /dev/zero character
|
|
special file results in a return value of the total number of bytes requested
|
|
to be written. No data is written to the character special file. In addition,
|
|
the change and modification times for the file are updated.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<p>If the write exceeds the process soft file size limit, signal SIFXFSZ is
|
|
issued.</p>
|
|
</li>
|
|
</ol>
|
|
|
|
<br>
|
|
<h3>Related Information</h3>
|
|
|
|
<ul>
|
|
<li>The <<strong>fcntl.h</strong>> file (see <a href="unix13.htm">Header
|
|
Files for UNIX-Type Functions</a>)
|
|
</li>
|
|
|
|
<li>The <<strong>unistd.h</strong>> file (see <a href="unix13.htm">Header
|
|
Files for UNIX-Type Functions</a>)
|
|
</li>
|
|
|
|
<li><a href="creat.htm">creat()</a>--Create or Rewrite File
|
|
</li>
|
|
|
|
<li><a href="dup.htm">dup()</a>--Duplicate Open File Descriptor
|
|
</li>
|
|
|
|
<li><a href="dup2.htm">dup2()</a>--Duplicate Open File Descriptor to Another
|
|
Descriptor
|
|
</li>
|
|
|
|
<li><a href="fclear.htm">fclear()</a>--Write (Binary Zeros) to Descriptor
|
|
</li>
|
|
|
|
<li><a href="fclear64.htm">fclear64()</a>--Write (Binary Zeros) to Descriptor
|
|
(Large File Enabled)</li>
|
|
|
|
<li><a href="fcntl.htm">fcntl()</a>--Perform File Control Command
|
|
</li>
|
|
|
|
<li><a href="ioctl.htm">ioctl()</a>--Perform I/O Control Request
|
|
</li>
|
|
|
|
<li><a href="lseek.htm">lseek()</a>--Set File Read/Write Offset
|
|
</li>
|
|
|
|
<li><a href="open.htm">open()</a>--Open File
|
|
</li>
|
|
|
|
<li><a href="read.htm">read()</a>--Read from Descriptor
|
|
</li>
|
|
|
|
<li><a href="readv.htm">readv()</a>--Read from Descriptor Using Multiple
|
|
Buffers
|
|
</li>
|
|
|
|
<li><a href="send.htm">send()</a>--Send Data
|
|
</li>
|
|
|
|
<li><a href="sendms.htm">sendmsg()</a>--Send Data or Descriptors or Both
|
|
</li>
|
|
|
|
<li><a href="sendto.htm">sendto()</a>--Send Data
|
|
</li>
|
|
|
|
<li><a href="write.htm">write()</a>--Write to Descriptor</li>
|
|
</ul>
|
|
|
|
<br>
|
|
<hr>
|
|
API introduced: V3R1
|
|
|
|
<hr>
|
|
<center>
|
|
<table cellpadding="2" cellspacing="2">
|
|
<tr align="center">
|
|
<td valign="middle" align="center"><a href="#Top_Of_Page">Top</a> | <a href=
|
|
"unix.htm">UNIX-Type APIs</a> | <a href="aplist.htm">APIs by category</a></td>
|
|
</tr>
|
|
</table>
|
|
</center>
|
|
</body>
|
|
</html>
|
|
|