PHP input/output stream

PHP 3.0.13 And later versions, from PHP 4.3.0 Startup support PHP: // output And PHP: // Input , From PHP 5.0.0 Startup support PHP: // Filter .

• PHP: // stdin

• PHP: // stdout

• PHP: // stderr

• PHP: // output

• PHP: // Input

• PHP: // Filter

PHP: // stdin,PHP: // stdoutAndPHP: // stderrAllow access to the input or output stream of the PHP process.

PHP: // outputAllows writing data to the output buffer, andPrint ()AndEcho ().

PHP: // InputAllows you to read original post data. And$ Http_raw_post_dataCompared to memory, it puts less pressure on memory and does not require any specialPHP. ini.

PHP: // stdinAndPHP: // InputIs read-only, at the same time,PHP: // stdout,PHP: // stderrAndPHP: // outputWrite-only.

PHP: // FilterIs designed to allow FiltersProgramIt is a stream Encapsulation Protocol when it is opened. This is for file functions that have individual complete functions, suchReadfile (),File ()AndFile_get_contents ()It is useful, otherwise it will not be able to apply the filter to the stream before reading the content.

PHP: // FilterThe target accepts the subsequent 'parameters' as part of its 'path.

• /Resource = <stream to be filtered>(Required) This parameter must be locatedPHP: // FilterAnd point to the stream to be filtered.

  <? PHP
/* This is equivalent to simply:
Readfile ("http://www.example.com ");
Since no filters are actually specified */
Readfile ("PHP: // filter/resource = http://www.example.com ");
?>

• /Read = <Filter list to apply to read chain>(Optional) This parameter accepts the names of one or more filters, using pipeline characters.|Separated.

  <? PHP
/* This will output the contents
Www.example.com entirely in uppercase */
Readfile ("PHP: // filter/read = string. toupper/resource = http://www.example.com ");
/* This will do the same as abve
But will also rot13 encode it */
Readfile ("PHP: // filter/read = string. toupper | string. rot13/resource = http://www.example.com ");
?>

• /Write = <Filter list to apply to write chain>(Optional) This parameter accepts the names of one or more filters, using pipeline characters.|Separated.

  <? PHP
/* This will filter the string "Hello World"
Through the rot13 filter, then write
Example.txt in the current directory */
File_set_contents ("PHP: // filter/Write = string. rot13/resource=example.txt", "Hello World ");
?>

• /<Filter list to apply to both chains>(Optional) AnyRead =OrWrite =The specified filter is applied to the read/write chain at the same time.

Table I-5. Wrapper Summary (PHP: // Filter, Refer to summary of wrapper being filtered .)

Attribute
Supported

RestrictedAllow_url_fopen.
No

Allows reading
PHP: // stdinAndPHP: // InputOnly.

Allows writing
PHP: // stdout,PHP: // stderr, AndPHP: // outputOnly.

Allows appending
PHP: // stdout,PHP: // stderr, AndPHP: // outputOnly. (equivalent to writing)

Allows simultaneous reading and writing
No. These wrappers are unidirectional.

SupportsStat ()
No

SupportsUnlink ()
No