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FTELL(3P)                  POSIX Programmer's Manual                 FTELL(3P)
PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the  corresponding
       Linux  manual page for details of Linux behavior), or the interface may
       not be implemented on Linux.
NAME
       ftell, ftello -- return a file offset in a stream
SYNOPSIS
       #include <stdio.h>
       long ftell(FILE *stream);
       off_t ftello(FILE *stream);
DESCRIPTION
       The functionality described on this reference page is aligned with  the
       ISO C  standard.  Any  conflict between the requirements described here
       and the ISO C standard is unintentional. This  volume  of  POSIX.1-2008
       defers to the ISO C standard.
       The  ftell()  function shall obtain the current value of the file-posi-
       tion indicator for the stream pointed to by stream.
       The ftell() function shall not change the setting of errno if  success-
       ful.
       The  ftello()  function shall be equivalent to ftell(), except that the
       return value is of type off_t and the ftello() function may change  the
       setting of errno if successful.
RETURN VALUE
       Upon  successful completion, ftell() and ftello() shall return the cur-
       rent value of the file-position indicator for the  stream  measured  in
       bytes from the beginning of the file.
       Otherwise, ftell() and ftello() shall return -1, and set errno to indi-
       cate the error.
ERRORS
       The ftell() and ftello() functions shall fail if:
       EBADF  The file descriptor  underlying  stream  is  not  an  open  file
              descriptor.
       EOVERFLOW
              For  ftell(), the current file offset cannot be represented cor-
              rectly in an object of type long.
       EOVERFLOW
              For ftello(), the current file offset cannot be represented cor-
              rectly in an object of type off_t.
       ESPIPE The file descriptor underlying stream is associated with a pipe,
              FIFO, or socket.
       The following sections are informative.
EXAMPLES
       None.
APPLICATION USAGE
       None.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       Section 2.5, Standard I/O Streams, fgetpos(), fopen(), fseek(), lseek()
       The Base Definitions volume of POSIX.1-2008, <stdio.h>
COPYRIGHT
       Portions of this text are reprinted and reproduced in  electronic  form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri-
       cal and Electronics Engineers,  Inc  and  The  Open  Group.   (This  is
       POSIX.1-2008  with  the  2013  Technical Corrigendum 1 applied.) In the
       event of any discrepancy between this version and the original IEEE and
       The  Open Group Standard, the original IEEE and The Open Group Standard
       is the referee document. The original Standard can be  obtained  online
       at http://www.unix.org/online.html .
       Any  typographical  or  formatting  errors that appear in this page are
       most likely to have been introduced during the conversion of the source
       files  to  man page format. To report such errors, see https://www.ker-
       nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group                  2013                            FTELL(3P)