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+/*
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the University of California, Berkeley. The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/*
+FUNCTION
+<<fread>>---read array elements from a file
+
+INDEX
+ fread
+
+ANSI_SYNOPSIS
+ #include <stdio.h>
+ size_t fread(void *<[buf]>, size_t <[size]>, size_t <[count]>,
+ FILE *<[fp]>);
+
+TRAD_SYNOPSIS
+ #include <stdio.h>
+ size_t fread(<[buf]>, <[size]>, <[count]>, <[fp]>)
+ char *<[buf]>;
+ size_t <[size]>;
+ size_t <[count]>;
+ FILE *<[fp]>;
+
+DESCRIPTION
+<<fread>> attempts to copy, from the file or stream identified by
+<[fp]>, <[count]> elements (each of size <[size]>) into memory,
+starting at <[buf]>. <<fread>> may copy fewer elements than
+<[count]> if an error, or end of file, intervenes.
+
+<<fread>> also advances the file position indicator (if any) for
+<[fp]> by the number of @emph{characters} actually read.
+
+RETURNS
+The result of <<fread>> is the number of elements it succeeded in
+reading.
+
+PORTABILITY
+ANSI C requires <<fread>>.
+
+Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
+<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
+*/
+
+#include <stdio.h>
+#include <string.h>
+#include "local.h"
+
+size_t
+_DEFUN (fread, (buf, size, count, fp),
+ _PTR buf _AND
+ size_t size _AND
+ size_t count _AND
+ FILE * fp)
+{
+ register size_t resid;
+ register char *p;
+ register int r;
+ size_t total;
+
+ if ((resid = count * size) == 0)
+ return 0;
+ if (fp->_r < 0)
+ fp->_r = 0;
+ total = resid;
+ p = buf;
+ while (resid > (r = fp->_r))
+ {
+ (void) memcpy ((void *) p, (void *) fp->_p, (size_t) r);
+ fp->_p += r;
+ /* fp->_r = 0 ... done in __srefill */
+ p += r;
+ resid -= r;
+ if (__srefill (fp))
+ {
+ /* no more input: return partial result */
+ return (total - resid) / size;
+ }
+ }
+ (void) memcpy ((void *) p, (void *) fp->_p, resid);
+ fp->_r -= resid;
+ fp->_p += resid;
+ return count;
+}