Get current file position for FILE stream.
- FILE stream to get the file position from.
Returns the current file offset if successful; otherwise -1 is returned and Stdlib.GetLastError indicates the error.
The following errors are specified:
Error Details Errno.EBADF The stream argument is not not a seekable stream Errno.EINVAL The whence argument is invalid or the resulting file-position indicator would be set to a negative value. Errno.EOVERFLOW The resulting file offset would be a value which cannot be represented correctly in an object of type stem.Int64 for Stdlib.fseek() and Stdlib.ftell(). Errno.ESPIPE The file descriptor underlying stream is associated with a pipe or FIFO or file-position indicator value is unspecified (see Stdlib.ungetc(3)).