Get current seekpointer on a filehandle

Daftar Isi

• tell FILEHANDLE

• tell

  Returns the current position in bytes for FILEHANDLE, or -1 onerror. FILEHANDLE may be an expression whose value gives the name ofthe actual filehandle. If FILEHANDLE is omitted, assumes the filelast read.

  Note the in bytes: even if the filehandle has been set tooperate on characters (for example by using the :encoding(utf8) openlayer), tell() will return byte offsets, not character offsets (becausethat would render seek() and tell() rather slow).

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

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

  Do not use tell() (or other buffered I/O operations) on a filehandlethat has been manipulated by sysread(), syswrite(), or sysseek().Those functions ignore the buffering, while tell() does not.