(PHP 4 >= 4.3.2, PHP 5, PHP 7, PHP 8)
streamWrapper::stream_seek — Seeks to specific location in a stream
$offset, int $whence = SEEK_SET): boolThis method is called in response to fseek().
The read/write position of the stream should be updated according to the
offset and whence.
offsetThe stream offset to seek to.
whencePossible values:
SEEK_SET - Set position equal to offset bytes.SEEK_CUR - Set position to current location plus offset.SEEK_END - Set position to end-of-file plus offset.注意: The current implementation never sets
whencetoSEEK_CUR; instead such seeks are internally converted toSEEK_SETseeks.
Return true if the position was updated, false otherwise.
注意:
If not implemented,
falseis assumed as the return value.
注意:
Upon success, streamWrapper::stream_tell() is called directly after calling streamWrapper::stream_seek(). If streamWrapper::stream_tell() fails, the return value to the caller function will be set to
false
注意:
Not all seeks operations on the stream will result in this function being called. PHP streams have read buffering enabled by default (see also stream_set_read_buffer()) and seeking may be done by merely moving the buffer pointer.
Please notice that the return value of this function is a boolean but the return value of fseek is 0 for ok and -1 for failure.
Please use this implementation when working with files:
function stream_seek($offset, $whence) {
if(0 === fseek($this->_handler, $offset, $whence)){
return true;
}
return false;
}