1FTELL(3P)                  POSIX Programmer's Manual                 FTELL(3P)
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PROLOG

6       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
7       implementation of this interface may differ (consult the  corresponding
8       Linux  manual page for details of Linux behavior), or the interface may
9       not be implemented on Linux.
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NAME

12       ftell, ftello - return a file offset in a stream
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SYNOPSIS

15       #include <stdio.h>
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17       long ftell(FILE *stream);
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20       off_t ftello(FILE *stream);
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DESCRIPTION

24       The ftell() function shall obtain the current value of  the  file-posi‐
25       tion indicator for the stream pointed to by stream.
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27       The  ftello()  function shall be equivalent to ftell(), except that the
28       return value is of type off_t.
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RETURN VALUE

31       Upon successful completion, ftell()  and  ftello()   shall  return  the
32       current value of the file-position indicator for the stream measured in
33       bytes from the beginning of the file.
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35       Otherwise, ftell()  and ftello()  shall return -1,  cast  to  long  and
36       off_t respectively, and set errno to indicate the error.
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ERRORS

39       The ftell()  and ftello()  functions shall fail if:
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41       EBADF  The  file  descriptor  underlying  stream  is  not  an open file
42              descriptor.
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44       EOVERFLOW
45              For ftell(), the current file offset cannot be represented  cor‐
46              rectly in an object of type long.
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48       EOVERFLOW
49              For ftello(), the current file offset cannot be represented cor‐
50              rectly in an object of type off_t.
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52       ESPIPE The file descriptor underlying stream is associated with a  pipe
53              or FIFO.
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56       The ftell() function may fail if:
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58       ESPIPE The  file  descriptor  underlying  stream  is  associated with a
59              socket.
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62       The following sections are informative.
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EXAMPLES

65       None.
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APPLICATION USAGE

68       None.
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RATIONALE

71       None.
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FUTURE DIRECTIONS

74       None.
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SEE ALSO

77       fgetpos(), fopen(), fseek(), lseek(), the Base  Definitions  volume  of
78       IEEE Std 1003.1-2001, <stdio.h>
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81       Portions  of  this text are reprinted and reproduced in electronic form
82       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
83       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
84       Specifications Issue 6, Copyright (C) 2001-2003  by  the  Institute  of
85       Electrical  and  Electronics  Engineers, Inc and The Open Group. In the
86       event of any discrepancy between this version and the original IEEE and
87       The  Open Group Standard, the original IEEE and The Open Group Standard
88       is the referee document. The original Standard can be  obtained  online
89       at http://www.opengroup.org/unix/online.html .
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93IEEE/The Open Group                  2003                            FTELL(3P)
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