This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface

       None.

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard
       for  Information  Technology  --  Portable  Operating  System  Interface  (POSIX),  The  Open  Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical  and  Electronics
       Engineers, Inc and The Open Group.  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.opengroup.org/unix/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.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                                   2017                                         FTELL(3POSIX)

       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.1‐2017 defers to the ISO C standard.

       The ftell() function shall obtain the current value of the file-position indicator for the stream pointed
       to by stream.

       The ftell() function shall not change the setting of errno if successful.

       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.

       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 correctly in an object of type long.

       EOVERFLOW
              For ftello(), the current file offset cannot be represented correctly in an object of type off_t.

       ESPIPE The file descriptor underlying stream is associated with a pipe, FIFO, or socket.

       Thefollowingsectionsareinformative.

       None.

       None.

       ftell, ftello — return a file offset in a stream

       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.

       None.

       Upon successful completion, ftell() and ftello() shall return the  current  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 indicate the error.

Section2.5, StandardI/OStreams, fgetpos(), fopen(), fseek(), lseek()

       The Base Definitions volume of POSIX.1‐2017, <stdio.h>

       #include <stdio.h>

       long ftell(FILE *stream);
       off_t ftello(FILE *stream);