No external libraries are needed to build this extension, but if you want PHP to support LFS (large files) on Linux, then you need to have a recent glibc and you need compile PHP with the following compiler flags: -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64.
There is no installation needed to use these functions; they are part of the PHP core.
The behaviour of these functions is affected by settings in php.ini.
Table 1. Filesystem and Streams Configuration Options
Name | Default | Changeable | Changelog |
---|---|---|---|
allow_url_fopen | "1" | PHP_INI_SYSTEM | PHP_INI_ALL in PHP <= 4.3.4. Available since PHP 4.0.4. |
allow_url_include | "0" | PHP_INI_SYSTEM | Available since PHP 5.2.0. |
user_agent | NULL | PHP_INI_ALL | Available since PHP 4.3.0. |
default_socket_timeout | "60" | PHP_INI_ALL | Available since PHP 4.3.0. |
from | "" | PHP_INI_ALL | |
auto_detect_line_endings | "0" | PHP_INI_ALL | Available since PHP 4.3.0. |
Here's a short explanation of the configuration directives.
allow_url_fopen
booleanThis option enables the URL-aware fopen wrappers that enable accessing URL object like files. Default wrappers are provided for the access of remote files using the ftp or http protocol, some extensions like zlib may register additional wrappers.
Note: This setting can only be set in php.ini due to security reasons.
Note: This option was introduced immediately after the release of version 4.0.3. For versions up to and including 4.0.3 you can only disable this feature at compile time by using the configuration switch
--disable-url-fopen-wrapper
.
Warning |
On Windows versions prior to PHP 4.3.0, the following functions do not support remote file accessing: include(), include_once(), require(), require_once() and the imagecreatefromXXX functions in the Reference LXV, Image Functions extension. |
allow_url_include
booleanThis option allows the use of URL-aware fopen wrappers with the following functions: include(), include_once(), require(), require_once().
Note: This setting requires allow_url_fopen to be on.
user_agent
stringDefine the user agent for PHP to send.
default_socket_timeout
integerDefault timeout (in seconds) for socket based streams.
Note: This configuration option was introduced in PHP 4.3.0
from
stringDefine the anonymous ftp password (your email address).
auto_detect_line_endings
booleanWhen turned on, PHP will examine the data read by fgets() and file() to see if it is using Unix, MS-Dos or Macintosh line-ending conventions.
This enables PHP to interoperate with Macintosh systems, but defaults to Off, as there is a very small performance penalty when detecting the EOL conventions for the first line, and also because people using carriage-returns as item separators under Unix systems would experience non-backwards-compatible behaviour.
Note: This configuration option was introduced in PHP 4.3.0
The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime.
Since PHP 5.2.0.
Since PHP 5.0.0. Search for filename
in
include_path.
Since PHP 5.0.0. Strips EOL characters.
Since PHP 5.0.0. Skips empty lines.
For related functions, see also the Directory and Program Execution sections.
For a list and explanation of the various URL wrappers that can be used as remote files, see also Appendix O.