newlib-2.4.0

git-svn-id: svn://kolibrios.org@6536 a494cfbc-eb01-0410-851d-a64ba20cac60

contrib/sdk/sources/newlib/libc/stdio/fsetpos.c

@@ -0,0 +1,95 @@
+/*
+ * 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
+<<fsetpos>>---restore position of a stream or file
+
+INDEX
+	fsetpos
+INDEX
+	_fsetpos_r
+
+ANSI_SYNOPSIS
+	#include <stdio.h>
+	int fsetpos(FILE *<[fp]>, const fpos_t *<[pos]>);
+	int _fsetpos_r(struct _reent *<[ptr]>, FILE *<[fp]>,
+	               const fpos_t *<[pos]>);
+
+TRAD_SYNOPSIS
+	#include <stdio.h>
+	int fsetpos(<[fp]>, <[pos]>)
+	FILE *<[fp]>;
+	fpos_t *<[pos]>;
+
+	int _fsetpos_r(<[ptr]>, <[fp]>, <[pos]>)
+	struct _reent *<[ptr]>;
+	FILE *<[fp]>;
+	fpos_t *<[pos]>;
+
+DESCRIPTION
+Objects of type <<FILE>> can have a ``position'' that records how much
+of the file your program has already read.  Many of the <<stdio>> functions
+depend on this position, and many change it as a side effect.
+
+You can use <<fsetpos>> to return the file identified by <[fp]> to a previous
+position <<*<[pos]>>> (after first recording it with <<fgetpos>>).
+
+See <<fseek>> for a similar facility.
+
+RETURNS
+<<fgetpos>> returns <<0>> when successful.  If <<fgetpos>> fails, the
+result is <<1>>.  The reason for failure is indicated in <<errno>>:
+either <<ESPIPE>> (the stream identified by <[fp]> doesn't support
+repositioning) or <<EINVAL>> (invalid file position).
+
+PORTABILITY
+ANSI C requires <<fsetpos>>, but does not specify the nature of
+<<*<[pos]>>> beyond identifying it as written by <<fgetpos>>.
+
+Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
+<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
+*/
+
+#include <_ansi.h>
+#include <reent.h>
+#include <stdio.h>
+
+int
+_DEFUN(_fsetpos_r, (ptr, iop, pos),
+       struct _reent * ptr _AND
+       FILE * iop          _AND
+       _CONST _fpos_t * pos)
+{
+  int x = _fseek_r (ptr, iop, *pos, SEEK_SET);
+
+  if (x != 0)
+    return 1;
+  return 0;
+}
+
+#ifndef _REENT_ONLY
+
+int
+_DEFUN(fsetpos, (iop, pos),
+       FILE * iop _AND
+       _CONST _fpos_t * pos)
+{
+  return _fsetpos_r (_REENT, iop, pos);
+}
+
+#endif /* !_REENT_ONLY */