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<p class=MsoNormal><span lang=EN-US>Hello,<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I’m trying to store additional metadata
like content-type and etc at extended attribute.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>My client code are like<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>fd = glusterfs_open( path );<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>glusterfs_write( fd, data, data_length );<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>glusterfs_close( fd );
//------<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>glusterfs_setxattr( path, attr_name,
attr_value, value_length,0 );<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>My concern is that above client code runs
on multiple machines and multi-threaded.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>In higher concurrency, client A could write
content, client B write content, client B write its attribute then client A
write its attribute.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>So to speak, file content comes from client
B but attribute comes from client A.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>If I use a lock server, I can guarantee
data integrity. But is there a simpler way to store extended attributes at an
atomic environment? <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I see another function, glusterfs_fsetxattr
which accepts open glusterfs_file descriptor. If I rewrite as following, can I
guarantee the integrity?<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>fd = glusterfs_open( path );<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>glusterfs_write( fd, data, data_length );<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>glusterfs_fsetxattr( fd, attr_name,
attr_value, value_length,0 );<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>glusterfs_close( fd ); <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>Thanks<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal align=left style='text-align:left;text-autospace:ideograph-numeric ideograph-other;
word-break:keep-all'><b><span lang=EN-US style='font-family:Gulim'>DongMin Yu</span></b><span
lang=EN-US style='font-size:12.0pt;font-family:Gulim'><o:p></o:p></span></p>
<p class=MsoNormal align=left style='text-align:left;text-autospace:ideograph-numeric ideograph-other;
word-break:keep-all'><span lang=EN-US style='font-size:12.0pt;font-family:Gulim'> <o:p></o:p></span></p>
<p class=MsoNormal align=left style='text-align:left;text-autospace:ideograph-numeric ideograph-other;
word-break:keep-all'><span lang=EN-US style='font-family:Gulim'>HOSTWAY IDC
Corp. / R&D Principal Researcher</span><span lang=EN-US style='font-size:
12.0pt;font-family:Gulim'><o:p></o:p></span></p>
<p class=MsoNormal align=left style='text-align:left;text-autospace:ideograph-numeric ideograph-other;
word-break:keep-all'><span lang=EN-US style='font-family:Gulim'>TEL. +822 2105
6037</span><span lang=EN-US style='font-size:12.0pt;font-family:Gulim'><o:p></o:p></span></p>
<p class=MsoNormal align=left style='text-align:left;text-autospace:ideograph-numeric ideograph-other;
word-break:keep-all'><span lang=EN-US style='font-family:Gulim'>FAX. +822 2105
6019</span><span lang=EN-US style='font-size:12.0pt;font-family:Gulim'><o:p></o:p></span></p>
<p class=MsoNormal align=left style='text-align:left;text-autospace:ideograph-numeric ideograph-other;
word-break:keep-all'><span lang=EN-US style='font-family:Gulim'>CELL. +8216
2086 1357</span><span lang=EN-US style='font-size:12.0pt;font-family:Gulim'><o:p></o:p></span></p>
<p class=MsoNormal align=left style='text-align:left;text-autospace:ideograph-numeric ideograph-other;
word-break:keep-all'><span lang=EN-US style='font-family:Gulim'>EMAIL: <a
href="mailto:min.yu@hostwaycorp.com"><span style='color:blue'>min.yu@hostwaycorp.com</span></a>
</span><span lang=EN-US style='font-size:12.0pt;font-family:Gulim'><o:p></o:p></span></p>
<p class=MsoNormal align=left style='text-align:left;text-autospace:ideograph-numeric ideograph-other;
word-break:keep-all'><span lang=EN-US style='font-family:Gulim'>Website: <a
href="http://www.hostway.com"><span style='color:blue'>http://www.hostway.com</span></a>
</span><span lang=EN-US style='font-size:12.0pt;font-family:Gulim'><o:p></o:p></span></p>
<p class=MsoNormal align=left style='text-align:left;text-autospace:ideograph-numeric ideograph-other;
word-break:keep-all'><span lang=EN-US style='font-size:12.0pt;font-family:Gulim'> <o:p></o:p></span></p>
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