◄Summary► ◄Example► ◄Up► ◄Contents► ◄Index► ◄Back► ─────Run-Time Library─────────────────────────────────────────────────────── The ftell function gets the current position of the file pointer (if any) associated with <stream>. The position is expressed as an offset relative to the beginning of the stream. Note that when a file is opened for appending data, the current file position is determined by the last I/O operation, not by the location of the next write. For example, if a file is opened for an append and the last operation was a read, the file position is the point where the next read operation would start, not where the next write would start. (When a file is opened for appending, the file position is moved to end-of-file before any write operation.) If no I/O operation has yet occurred on a file opened for appending, the file position is the beginning of the file. Return Value The ftell function returns the current file position. The value returned by ftell may not reflect the physical byte offset for streams opened in text mode, since text mode causes carriage- return─linefeed translation. Use ftell in conjunction with the fseek function to return to file locations correctly. On error, the function returns -1L. Also, errno is set to one of the following constants (defined in ERRNO.H): EBADF or EINVAL. The return value is undefined on devices incapable of seeking (such as terminals and printers) or when <stream> does not refer to an open file. -♦-