ack/lang/cem/libcc.ansi/sys/stdio/ftell.c

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/*
* ftell.c - obtain the value of the file-position indicator of a stream
*/
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/* $Id$ */
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#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
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#include "loc_incl.h"
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#if ACKCONF_WANT_STDIO
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long ftell(FILE* stream)
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{
long result;
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int adjust = 0;
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if (io_testflag(stream, _IOREADING))
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adjust = -stream->_count;
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else if (io_testflag(stream, _IOWRITING)
&& stream->_buf
&& !io_testflag(stream, _IONBF))
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adjust = stream->_ptr - stream->_buf;
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else
adjust = 0;
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result = lseek(fileno(stream), 0, SEEK_CUR);
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if (result == -1)
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return result;
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result += (long)adjust;
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return result;
}
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#endif