Description
bool
dio_truncate ( resource fd, int offset)
Function dio_truncate() causes the file
referenced by fd to be truncated to at
most offset bytes in size. If the file
previously was larger than this size, the extra data is lost. If
the file previously was shorter, it is unspecified whether the
file is left unchanged or is extended. In the latter case the
extended part reads as zero bytes. 如果成功则返回 TRUE,失败则返回 FALSE。.