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/* **********************************************
* *
* header file file descriptor (FD) code *
* *
* James Peterson, 1987 *
* Copyright (C) 1987 MCC
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that
* copyright notice and this permission notice appear in supporting
* documentation, and that the name of MCC not be used in
* advertising or publicity pertaining to distribution of the software without
* specific, written prior permission. MCC makes no
* representations about the suitability of this software for any purpose. It
* is provided "as is" without express or implied warranty.
*
* MCC DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
* EVENT SHALL MCC BE LIABLE FOR ANY SPECIAL, INDIRECT OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
* DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
* TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
* *
********************************************** */
/*
the following structure remembers for each file descriptor its
state. In particular, we need to know if it is busy or free
and if it is in use, by whom.
*/
typedef int FD;
struct FDDescriptor
{
Boolean Busy;
int (*InputHandler)();
int (*FlushHandler)();
};
extern struct FDDescriptor *FDD /* array of FD descriptors */ ;
extern short MaxFD /* maximum number of FD's possible */ ;
extern short nFDsInUse /* number of FD's actually in use */ ;
extern long ReadDescriptors /* bit map of FD's in use -- for select */ ;
extern long WriteDescriptors /* bit map of write blocked FD's -- for select */;
extern long BlockedReadDescriptors /* bit map of FD's blocked from reading */;
extern short HighestFD /* highest FD in use -- for select */ ;
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