doc/html/ref/tcpip-openbsd-enhanced-select.html

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  85 NAME="TCPIP-OPENBSD-ENHANCED-SELECT">Enhanced Select()</H1
  86 ><P
  87 >The network stack supports an extension to the standard select
  88 semantics which allows all threads that are waiting to be restarted
  89 even if the select conditions are not satisfied.</P
  90 ><P
  91 >The standard select() API:  </P
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  98 ><PRE
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 100 >int
 101 <TT
 102 CLASS="FUNCTION"
 103 >select</TT
 104 >(int nfd,
 105        fd_set &#0042;in, fd_set &#0042;out, fd_set &#0042;ex,
 106        struct timeval &#0042;tv); </PRE
 107 ></TD
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 109 ></TABLE
 110 ><P
 111 >does not support the restart.</P
 112 ><P
 113 >The additional API:  </P
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 121 CLASS="PROGRAMLISTING"
 122 >int
 123 <TT
 124 CLASS="FUNCTION"
 125 >cyg_select_with_abort</TT
 126 >(int nfd,
 127        fd_set &#0042;in, fd_set &#0042;out, fd_set &#0042;ex,
 128        struct timeval &#0042;tv)</PRE
 129 ></TD
 130 ></TR
 131 ></TABLE
 132 ><P
 133 >behaves exactly as select() with the additional feature that
 134 a call to</P
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 142 CLASS="PROGRAMLISTING"
 143 >void <TT
 144 CLASS="FUNCTION"
 145 >cyg_select_abort</TT
 146 >(void)</PRE
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 149 ></TABLE
 150 ><P
 151 >will cause all threads waiting in any
 152 <TT
 153 CLASS="FUNCTION"
 154 >cyg_select_with_abort()</TT
 155 > call
 156 to cease waiting and continue execution.</P
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