=over

=item tell FILEHANDLE

=item tell

Returns the current position for FILEHANDLE, or -1 on error.  FILEHANDLE
may be an expression whose value gives the name of the actual filehandle.
If FILEHANDLE is omitted, assumes the file last read.  

The return value of tell() for the standard streams like the STDIN
depends on the operating system: it may return -1 or something else.
tell() on pipes, fifos, and sockets usually returns -1.

There is no C<systell> function.  Use C<sysseek(FH, 0, 1)> for that.

=back