46 lines
1.2 KiB
C
46 lines
1.2 KiB
C
/*-
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* LstFirst.c --
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* Return the first node of a list
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*
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* Copyright (c) 1988 by University of California Regents
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*
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* Permission to use, copy, modify, and distribute this
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* software and its documentation for any purpose and without
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* fee is hereby granted, provided that the above copyright
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* notice appears in all copies. Neither the University of California nor
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* Adam de Boor makes any representations about the suitability of this
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* software for any purpose. It is provided "as is" without
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* express or implied warranty.
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*/
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#if !defined(lint) && defined(keep_rcsid)
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static char *rcsid =
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"Id: lstFirst.c,v 1.5 88/11/17 20:52:44 adam Exp $ SPRITE (Berkeley)";
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#endif lint
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#include "lstInt.h"
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/*-
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*-----------------------------------------------------------------------
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* Lst_First --
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* Return the first node on the given list.
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*
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* Results:
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* The first node or NILLNODE if the list is empty.
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*
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* Side Effects:
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* None.
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*
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*-----------------------------------------------------------------------
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*/
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LstNode
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Lst_First (l)
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Lst l;
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{
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if (!LstValid (l) || LstIsEmpty (l)) {
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return (NILLNODE);
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} else {
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return ((LstNode)((List)l)->firstPtr);
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}
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}
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