XXV. Direct IO Functions


PHP supports the direct io functions as described in the Posix Standard (Section 6) for performing I/O functions at a lower level than the C-Language stream I/O functions (fopen(), fread(),..). The use of the DIO functions should be considered only when direct control of a device is needed. In all other cases, the standard filesystem functions are more than adequate.

This extension is only available on Windows Platforms as of PHP 5.0.0


No external libraries are needed to build this extension.


To get these functions to work, you have to configure PHP with --enable-dio.

Runtime Configuration

This extension has no configuration directives defined in php.ini.

Resource Types

One resource type is defined by this extension: a file descriptor returned by dio_open().

Predefined Constants

This extension has no constants defined.

Table of Contents
dio_close -- Closes the file descriptor given by fd
dio_fcntl -- Performs a c library fcntl on fd
dio_open --  Opens a new filename with specified permissions of flags and creation permissions of mode
dio_read --  Reads n bytes from fd and returns them, if n is not specified, reads 1k block
dio_seek -- Seeks to pos on fd from whence
dio_stat --  Gets stat information about the file descriptor fd
dio_tcsetattr --  Sets terminal attributes and baud rate for a serial port
dio_truncate --  Truncates file descriptor fd to offset bytes
dio_write --  Writes data to fd with optional truncation at length