Php/docs/function.eio-sync-file-range
eio_sync_file_range
(PECL eio >= 0.0.1dev)
eio_sync_file_range — Sync a file segment with disk
说明
eio_sync_file_range
( mixed $fd
, int $offset
, int $nbytes
, int $flags
[, int $pri = EIO_PRI_DEFAULT
[, callable $callback = NULL
[, mixed $data = NULL
]]] ) : resource
eio_sync_file_range() permits fine control when synchronizing the open file referred to by the file
descriptor fd with disk.
参数
fdFile descriptor
offsetThe starting byte of the file range to be synchronized
nbytesSpecifies the length of the range to be synchronized, in bytes. If
nbytesis zero, then all bytes fromoffsetthrough to the end of file are synchronized.flagsA bit-mask. Can include any of the following values:
EIO_SYNC_FILE_RANGE_WAIT_BEFORE,EIO_SYNC_FILE_RANGE_WRITE,EIO_SYNC_FILE_RANGE_WAIT_AFTER. These flags have the same meaning as their SYNC_FILE_RANGE_* counterparts(seeSYNC_FILE_RANGE(2)man page).pri请求的优先级:
EIO_PRI_DEFAULT,EIO_PRI_MIN,EIO_PRI_MAX或null。如果是null,pri将设为EIO_PRI_DEFAULT。callbackcallback函数在请求完成时被调用。其应匹配一下原型:void callback(mixed $data, int $result[, resource $req]);data传递给请求的用户数据。
result针对请求的结果的值。通常是相应的系统调用返回的值。
req可选的请求资源,可被 eio_get_last_error() 之类的函数使用。
dataArbitrary variable passed to
callback.
返回值
eio_sync_file_range() returns request resource on success or false on error.