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[[!meta copyright="Copyright © 2010, 2014 Free Software Foundation, Inc."]]
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document under the terms of the GNU Free Documentation License, Version 1.2 or
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Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license
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License|/fdl]]."]]"""]]
A [[UNIX file descriptor|unix/file_descriptor]] is implemented in [[glibc]] by
using operations on objects referred to by [[Mach
ports|microkernel/mach/port]]).
# IRC, freenode, #hurd, 2013-11-29
[[!tag open_issue_documentation]]
<gnu_srs> Hi, are there any advantages to use the __USEPORT and
HURD_DPORT_USE etc macros?
<braunr> some things don't work without htem
<teythoon> I wondered that too
<teythoon> could you be more specific ?
<braunr> i can try
<braunr> __USEPORT is merely a wrapper to HURD_DPORT_USE
<braunr> HURD_PORT_USE handles concurrent access to ports
<braunr> is that enough ?
<teythoon> so not using these makes loading the port name racy ?
<braunr> shared ones, yes
<braunr> mostly, file descriptors
<teythoon> ok
<teythoon> so yes, that's reason enough ;)
<gnu_srs> so even if file descriptor ports are not accessed, it's use is
preferred?
<gnu_srs> I assume the answer is yes:-D
<braunr> gnu_srs: not accessed ?
<gnu_srs> file descriptor ports not used, but e.g. auth ports
<gnu_srs> there is code in hurd and eglibc sometimes using the macros,
sometimes not
<braunr> the macro is used when ports are shared
<braunr> or can be shared
<gnu_srs> k!, thanks
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