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@node select
@section @code{select}
@findex select

POSIX specification: @url{http://www.opengroup.org/susv3xsh/select.html}

Gnulib module: select

Portability problems fixed by Gnulib:
@itemize
@item
On Windows platforms (excluding Cygwin), @code{select} can only be
called on descriptors created by the @code{socket} function, not on regular
file descriptors.
@item
On Windows platforms (excluding Cygwin), error codes for @code{accept} are not
placed in @code{errno}, and @code{WSAGetLastError} must be used instead.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
When you call @code{select} with a timeout, some implementations modify the
timeout parameter so that upon return from the function, it contains the
amount of time not slept.  Other implementations leave the timeout parameter
unmodified.
@item
On BeOS, @code{select} can only be called on descriptors created by the
@code{socket} function, not on regular file descriptors.
@item
On Linux, when some file descriptor refers to a regular file, @code{select}
may fail, setting @code{errno} to @code{EBADF}.
@end itemize