Please note that dio_open()/dio_write()/dio_close() is *faster* than fopen()/fwrite()/fclose() for files.
fwrite() has to manage a 8k buffer, while dio_write() just issue a single write(). The end result is less system calls and less memory access.
Also, giving the full size to write() as with dio_write() let filesystems properly use preallocation in order to avoid fragmentation.
dio_open
(PHP 4 >= 4.2.0, PHP 5 <= 5.0.4)
dio_open -- Opens a new filename with specified permissions of flags and creation permissions of mode说明
resource dio_open ( string filename, int flags [, int mode] )dio_open() opens a file and returns a new file descriptor for it.
参数
- filename
The opened file.
- flags
The flags parameter can also include any combination of the following flags:
O_CREAT - creates the file, if it doesn't already exist.
O_EXCL - if both, O_CREAT and O_EXCL are set, dio_open() fails, if the file already exists.
O_TRUNC - if the file exists, and its opened for write access, the file will be truncated to zero length.
O_APPEND - write operations write data at the end of the file.
O_NONBLOCK - sets non blocking mode.
- mode
If flags is O_CREAT, mode will set the mode of the file (creation permissions).
O_RDONLY - opens the file for read access.
O_WRONLY - opens the file for write access.
O_RDWR - opens the file for both reading and writing.
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User Contributed Notes
j at pureftpd dot org
24-Jan-2005 08:13
24-Jan-2005 08:13
alla at cyber dot com dot au
22-Mar-2003 11:16
22-Mar-2003 11:16
To specify a combination of flags you OR them together.
This was the only way I could get it to append:
$fd = dio_open($file, O_WRONLY | O_APPEND);