Red Hat ENTERPRISE LINUX 5.5 - S 2010, Manual

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Chapter 1. Package Updates
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for asynchronous I/O. The POSIX asynchronous I/O facility requires this library in order to provide
kernel-accelerated asynchronous I/O capabilities, as do applications which require the Linux-native
asynchronous I/O API.
Red Hat Enterprise Linux lacked support for eventfd, which generates file descriptors. These
descriptors are used to provide an event wait/notify mechanism for userspace applications. eventfd
has now been added to the API and integrated with Asynchronous Input/Output (AIO). It eliminates
the need to use pipes to signal events, reducing kernel overhead as it does not consume two file
descriptors each time, as the previous method did. eventfd also offers an fd-bridge and can be used
to signal the readiness of interfaces that would otherwise be incompatible with the Linux kernel.
(
BZ#540626
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)
Users are advised to upgrade to this updated libaio package, which adds this enhanced functionality.
[Kernel update needed: RHBA-2009:9260]
1.100. libcmpiutil
1.100.1. RHBA-2010:0222: bug fix and enhancement update
An updated libcmpiutil package that fixes bugs and introduces feature enhancements is now available.
libcmpiutil provides a convenient API for performing common tasks with different CMPI providers.
* the libcmpiutil package is used by the libvirt-cim package. An update to the libvirt-cim package
requires this update. (
BZ#540843
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)
Users are advised to upgrade to this updated libcmpiutil package, which resolves these issues and
adds these enhancements.
1.101. libevent
1.101.1. RHEA-2010:0244: enhancement update
An updated libevent package that rebases to the current stable upstream release is now available.
The libevent API provides a mechanism to execute a callback function when a specific event occurs
on a file descriptor or after a timeout has been reached. libevent is meant to replace the asynchronous
event loop found in event driven network servers. An application just needs to call event_dispatch()
and can then add or remove events dynamically without having to change the event loop.
This update rebases the libevent library included with Red Hat Enterprise Linux from version 1.1a to
the current stable upstream release, version 1.4.13. (
BZ#476557
1345
)
For details on the changes between these two versions see the upstream Changelogs available on the
libevent home page:
http://monkey.org/~provos/libevent/
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https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=540626
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https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=540843
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https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=476557