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.\"
.\" libexplain - Explain errno values returned by libc functions
.\" Copyright (C) 2008-2011, 2013 Peter Miller
.\" Written by Peter Miller <pmiller@opensource.org.au>
.\"
.\" This program is free software; you can redistribute it and/or modify
.\" it under the terms of the GNU General Public License as published by
.\" the Free Software Foundation; either version 3 of the License, or (at
.\" your option) any later version.
.\"
.\" This program is distributed in the hope that it will be useful,
.\" but WITHOUT ANY WARRANTY; without even the implied warranty of
.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
.\" General Public License for more details.
.\"
.\" You should have received a copy of the GNU General Public License
.\" along with this program. If not, see <http://www.gnu.org/licenses/>.
.\"
.ad l
.hy 0
.nf
.so etc/version.so
<!DOCTYPE HTML PUBLIC
"-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/1999/REC-html401-19991224/loose.dtd"
>
<html>
<head>
<title>
libexplain \*(v)
</title>
</head>
<body background="bg.png">
<img src="libexplain.128.png" align="left" alt="" />
<img src="libexplain.128.png" align="right" alt="" />
<h1 align="center">
libexplain \*(v)
</h1>
The libexplain project provides a library which may be used to explain
Unix and Linux system call errors.
This will make your application's error messages much more
informative to your users.
<p>
The library is not quite a drop-in replacement for strerror, but it
comes close.
Each system call has a dedicated libexplain function, for example
<blockquote><pre>
fd = open(path, flags, mode);
if (fd < 0)
{
fprintf(stderr, "%s\en", <a
href="doc-external/open_8h.html#7c0bfc9a553438096c19b86dab687b2a"
>explain_open</a>(path, flags, mode));
exit(EXIT_FAILURE);
}
</pre></blockquote>
<p>
<table align="right" width="30%" ><tr bgcolor="#eeeebb" ><td><img
src="http://miller.emu.id.au/pmiller/images/kfish-64.png" alt="" ></td><td>
<small>‘I think it's totally awesome, in the category
of “why hasn't this existed for <i>n</i> years”
awesome.’ — <a href="http://www.kfish.org/"
>Parker san</a></small></td></tr>
</table>
If, for example, you were to try to open
<tt>no-such-dir/some-file</tt>, you would see a message like
<blockquote>
<tt>open(pathname = "no-such-dir/some-file", flags = O_RDONLY)
failed, No such file or directory (2, ENOENT) because there is no
"no-such-dir" directory in the current directory</tt>
</blockquote>
<p>
The good news is that for each of these functions there is a wrapper
function, in this case <a
href="doc-external/open_8h.html#ef4b43a41f11f51b07aa6a6162ad5bc1"
><i>explain_open_or_die</i>(3)</a>,
that includes
the above code fragment. Adding good error reporting is as simple as
using a different, but similarly named, function.
The library also provides thread safe variants of each explanation function.
<p>
The coverage for system calls is being improved all the time, as you can
see from <a href="doc-external/files.html" >this documentation page</a>
generated from the source code.
.so etc/coverage.so
<h2>
<img src="watch2.128.png" align="right" alt="" />
Documentation </h2>
<ul>
<li> The LCA 2010 talk, “<i>No medium found: when it's time to stop
trying to read strerror's mind</i>” is a available as
<a href="lca2010/lca2010.pdf" >PDF</a>, and the slides are available as
<a href="lca2010/index.html" >HTML</a>.
<li>
There is <a href="doc-external/index.html"
>full documentation</a> of all API functions.
This is the interface users of the library may use.
<li>
There is <a href="doc-internal/index.html"
>full documentation</a> of all internal functions.
This includes all of the functions internal to the library,
for libexplain developers to use.
<li>
The above documentation is generated from the source files,
via <a href="http://www.doxygen.org/index.html" >Doxygen</a>.
<li> Want to help? <a href="fixme.html" >Here is a list of places</a>
in the source code marked “FIXME”.
</ul>
<br clear="right" />
<h2>
Download </h2>
<p>
<table align="right" width="30%" >
<tr bgcolor="#eeeebb" >
<td>
<small>“pmiller read the kernel source so you don't have to”
— Rob Weir </small
</td
</tr>
</table>
There are several ways you can obtain the software, as either source
code or pre-compiled binaries.
<p>
<table>
<tr>
<td valign="top" align="center" >
<img src="libexplain.64.png" alt="[*]" />
</td>
<td valign="top" ><b>Master Sources</b><br/>
<p>
The following files are available for download from this web site:
<p>
<table>
<tr>
<th>File</th>
<th>Description</th>
</tr>
<tr>
<td nowrap>
<a href="libexplain-\*(V).README"
>libexplain-\*(V).README</a>
</td>
<td>
The README file form the tarball.
</td>
</tr>
<tr>
<td nowrap>
<a href="libexplain-\*(V).tar.gz"
>libexplain-\*(V).tar.gz</a>
</td>
<td>
The complete source.</td>
</tr>
<tr>
<td nowrap>
<a href="libexplain-\*(V).pdf" >libexplain-\*(V).pdf</a>
</td>
<td>
The reference manual, in PDF format.</td>
</tr>
</table>
<p><br/>
</td>
</tr>
<tr>
<td valign="top" align="center" >
<a href="https://sourceforge.net/projects/libexplain/files/" ><img
src="sf.png" border=0 alt="[*]" /></a>
</td>
<td valign="top" ><b>Sourceforge Downloads </b><br/>
<ul>
<li> The best possible download speed for the source tarball will be
from the <a
href="https://sourceforge.net/projects/libexplain/files/"
>SourceForge download pages</a>
<li> here is the <a
href="http://sourceforge.net/projects/libexplain/files/\
\*(v)/libexplain-\*(V).tar.gz/download"
>most recent tarball</a> from there.
</ul>
<p><br/>
</td>
</tr>
<tr>
<td valign="top" align="center" >
<a href="https://launchpad.net/~pmiller-opensource/+archive/ppa" ><img
src="https://launchpad.net/@@/launchpad-logo.png" border=0 alt="[*]"
/></a></td>
<td valign="top" ><b>Ubuntu Packages</b><br/>
<p>
If you use Ubuntu Linux, there are pre-built packages available for
installation using the normal <tt>sudo apt-get install</tt> method,
from <a href="https://launchpad.net/~pmiller-opensource/+archive/ppa"
>this package archive</a> (<a
href="https://help.launchpad.net/Packaging/PPA" >PPA</a>).
<p>
Instructions are available there for how to manually add the PPA to your
<tt>/etc/apt/sources.list</tt> file, but the following commands are
sufficient on recent versions of Ubuntu:
<blockquote>
<pre>sudo add-apt-repository ppa:pmiller-opensource/ppa
sudo apt-get update
sudo apt-get install libexplain-dev</pre>
</blockquote>
<p><br/>
</td>
</tr>
<tr>
<td valign="top" align="center" >
<img src="http://srecord.sourceforge.net/debian.png" alt="[*]" />
</td>
<td valign="top" ><b>Debian Packages</b><br/>
<ul>
<li> The libexplain project is <a
href="http://packages.debian.org/search?keywords=libexplain&\
searchon=names&suite=all&section=all"
>available</a> as part of Debian Linux.
<li> The libexplain project is <a
href="http://packages.ubuntu.com/search?keywords=libexplain&\
searchon=names&suite=all&section=all"
>available</a> as part of Ubuntu Linux.
<li> The most recent version is usually available <a
href="https://launchpad.net/~pmiller-opensource/+archive/ppa"
>from the PPA</a>.
<li> This web site also provides <a href="debian/"
>pre-built Debian packages</a> for
.so etc/lsb-release.so
</ul>
<p><br/>
</td>
</tr>
<tr>
<td valign="top" align="center" >
<a href="http://aegis.sourceforge.net/" ><img
src="http://aegis.sourceforge.net/aegis.png"
border=0 alt="[*]" /></a>
</td>
<td valign="top" ><b>Aegis</b><br/>
<ul>
<li> Libexplain is developed using <a
href="http://aegis.sourceforge.net/" >Aegis</a> DVCS
<li> The Aegis <a
href="http://aegis.sourceforge.net/cgi-bin/aeget/libexplain.\*(v)?menu"
>repository</a> for this project is available.
<li> The complete source is <a href="libexplain-\*(V).ae"
>available</a> in <i>aedist</i>(1) format.
</ul>
</td>
</tr>
</table>
.\" ------------------------------------------------------------------------
<hr/>
<h2>
<img src="orrery1.128.png" align="right" alt="" />
Services provided by SourceForge </h2>
<ul>
<li>
Mailing list is <a
href="mailto:libexplain-users@lists.sourceforge.net"
>libexplain-users@lists.sourceforge.net</a>, and you can subscribe <a
href="https://lists.sourceforge.net/lists/listinfo/libexplain-users"
>here</a>.
<li>
SourceForge <a href="http://sourceforge.net/projects/libexplain/"
>project</a> page.
<li>
SourceForge <a
href="http://sourceforge.net/projects/libexplain/files/" >download</a> page,
and most recent <a
href="http://sourceforge.net/project/platformdownload.php?group_id=241772"
>tarball</a> link.
<li>
SourceForge <a href="https://sourceforge.net/tracker/?group_id=241772"
>trackers</a> page: the <a
href="https://sourceforge.net/tracker/?\
atid=1117296&group_id=241772&func=browse"
>bug tracker</a>, the <a
href="http://sourceforge.net/tracker/?\
atid=1117298&group_id=241772&func=browse"
>patch tracker</a>, and <a
href="http://sourceforge.net/tracker/?\
atid=1117299&group_id=241772&func=browse"
>feature requests</a>.
</ul>
<h2> Services provided by Debian </h2>
<ul>
<li> Debian main <a
href="https://buildd.debian.org/pkg.cgi?pkg=libexplain&dist=unstable"
>build farm</a>
<li> Debian ports <a
href="http://buildd.debian-ports.org/status/package.php?\
suite=unstable&p=libexplain"
>build farm</a>.
</ul>
.\" ------------------------------------------------------------------------
<hr>
<table border=0>
<tr>
<td valign="top">
<a href="http://www.fsf.org/" ><img
src="http://upload.wikimedia.org/wikipedia/commons/b/bf/\
GNU-FDL-ic%C3%B4ne-Transparente.PNG"
border=0 width=129 height=122 alt="" /></a>
</td>
<td valign="top" width="35%" >
Libexplain is written and owned by
<a href="mailto:pmiller@opensource.org.au"
>Peter Miller <pmiller@opensource.org.au></a>
and is freely distributable under the terms and conditions of the
<a href="http://www.gnu.org/licenses/lgpl.txt">GNU LGPL</a>,
so you may use libexplain with proprietary programs.
</td>
<td valign="top">
<a href="http://www.opensource.org/docs/definition.php" ><img
src="http://www.opensource.org/trademarks/opensource/web/transparent/\
opensource-110x95-t.png"
border="0" width="110" height="95" alt="" /></a>
</td>
<td valign="top" align="right">
There is more <a href="http://miller.emu.id.au/pmiller/software/"
>Software by Peter Miller</a> at his home page.
</td>
<td valign="top">
<a href="http://miller.emu.id.au/pmiller/" ><img
src="http://miller.emu.id.au/pmiller/pmiller_2003_colour.64.png"
border=0 alt="" /></a>
</td>
</tr>
</table>
.\" ------------------------------------------------------------------------
<hr/>
<a href="http://sourceforge.net/"><img
src="http://sourceforge.net/sflogo.php?group_id=237324&type=5"
width="210" height="62" border="0" alt="SourceForge.net Logo"
align="right"></a>
This page is hosted by <a href="http://sourceforge.net/">SourceForge</a>.
<br>
This page has been accessed approximately
<img
src="http://miller.emu.id.au/cgi-bin/web_hit_counter?pmiller_libexplain_\*(v)"
alt="number" /> times since
.ds MO1 Jan
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.nr y4 \n[yr]+1900
\n[dy]-\*[MO\n[mo]]-\n[y4].
</body>
</html>
.\" vim: set ts=8 sw=4 et :
|
