[int$offset = 0],
[int$pri = EIO_PRI_DEFAULT],
[callable$callback = NULL],
[mixed$data = NULL]
eio_truncate causes the regular file named by path to be truncated to a size of precisely length bytes
Offset from beginning of the file.
The request priority: EIO_PRI_DEFAULT, EIO_PRI_MIN, EIO_PRI_MAX, or null. If null passed, pri internally is set to EIO_PRI_DEFAULT.
callback function is called when the request is done. It should match the following prototype:
void callback(mixed $data, int $result[, resource $req]);
is custom data passed to the request.
request-specific result value; basically, the value returned by corresponding system call.
is optional request resource which can be used with functions like eio_get_last_error
Arbitrary variable passed to callback.
eio_busy returns request resource on success, or false on failure.