php|architect's Guide to Web Scraping with PHP - Wind Business ...

Chapter 5
pecl_http P ECL Extension
The pecl_http extension became available in PHP 5 and gained a class for HTTP responses
in PHP 5.1. Like the cURL extension, it also wraps the libcurl library and
has similar advantages as a result, such as its internal DNS cache. While the cURL
extension uses resources and configuration options to more closely mimic libcurl’s
o wn API, the pecl_http extension offers the same features in the form of procedural
and object-oriented APIs. As a result, code that uses pecl_http is generally shorter
than equivalent code using the cURL extension.
Another major difference is that the cURL extension is considered to be part of the
PHP core, which means that it is more likely to be present in most environments
supporting PHP. In contrast, pecl_http must be installed via the pecl installer or
compiled manually from source. In either case, the extension requires the PHP and
libcurl development headers to be present in order to compile properly. N ot technically
being part of the PHP core, it is less likely to be present or available in shared
hosting environments depending on the hosting pro vider. This may be a concern for
code that is intended to be distributed for use in a variety of environments.
To install pecl_http via the pecl installer, PEAR must be installed (see
http://pear.php.net/manual/en/installation.php). A package for PEAR may also be
available through your OS package manager. Once it is installed, simply issue the
command pecl install pecl_http. To install from source, do wnload the latest version
from http://pecl.php.net/get/pecl_http. N ote that this requires the header
files for the PHP version you are using, which are contained in the PHP source tar-