@node ftello
@subsection @code{ftello}
@findex ftello

POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9799919799/functions/ftello.html}

Gnulib module: ftello
@mindex ftello

Portability problems fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
mingw, MSVC 14.
@item
The declaration of @code{ftello} in @code{<stdio.h>} is not enabled by default
on some platforms:
glibc 2.3.6.
@item
This function produces incorrect results after @code{putc} that followed a
@code{getc} call that reached EOF on some platforms:
Solaris 11 2010-11.
@item
This function, when invoked after @code{ungetc}, throws away the @code{ungetc}
buffer, changes the stream's file position, and returns the wrong position on
some platforms:
macOS 10.15, 11, 12.
@item
This function fails on seekable stdin, stdout, and stderr: cygwin <= 1.5.24.
@item
This function mistakenly succeeds on pipes on some platforms:
mingw 10.
@item
On platforms where @code{off_t} is a 32-bit type, @code{ftello} does not work
correctly with files 2 GiB and larger.  @xref{Large File Support}.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
This function produces incorrect results immediately after @code{fseek} on some
platforms:
HP-UX 11.
@item
@code{fflush}, @code{ftell}, @code{ftello}, @code{fgetpos} behave incorrectly
on input streams that are opened in @code{O_TEXT} mode and whose contents
contains Unix line terminators (LF), on some platforms: mingw, MSVC 14.
@end itemize
