Php/docs/function.eio-fallocate
eio_fallocate
(PECL eio >= 0.0.1dev)
eio_fallocate — Allows the caller to directly manipulate the allocated disk space for a file
说明
eio_fallocate
( mixed $fd
, int $mode
, int $offset
, int $length
[, int $pri
= EIO_PRI_DEFAULT
[, callable $callback
= NULL
[, mixed $data
= NULL
]]] ) : resource
eio_fallocate() allows the caller to directly manipulate the allocated disk space for the
file specified by fd
file descriptor for the byte
range starting at offset
and continuing for
length
bytes.
Note:
File should be opened for writing
EIO_O_CREAT
should be logically OR'd withEIO_O_WRONLY
, orEIO_O_RDWR
参数
fd
Stream, Socket resource, or numeric file descriptor, e.g. returned by eio_open().
mode
Currently only one flag is supported for mode:
EIO_FALLOC_FL_KEEP_SIZE
(the same as POSIX constantFALLOC_FL_KEEP_SIZE
).offset
Specifies start of the byte range.
length
Specifies length the byte range.
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
。callback
callback
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。
data
Arbitrary variable passed to
callback
.
返回值
eio_fallocate() returns request resource on success or false
on error.