Input/output streams

Quite early in development, every programmer stumbles upon the streams term. This seemingly frightening term represents a form of data. Unlike the typical finite type of data, streams represent a potentially unlimited sequence of data. In PHP terms, a stream is a resource object exhibiting streamable behavior. Using various wrappers, the PHP language supports a wide range of streams. The stream_get_wrappers() function can retrieve a list of all the registered stream wrappers available on the currently running system, such as the following:

• php
• file
• glob
• data
• http
• ftp
• zip
• compress.zlib
• compress.bzip2
• https
• ftps
• phar

The list of wrappers is quite extensive, but not finite. We can also register our own wrappers using the stream_wrapper_register() function. Each wrapper tells the stream how to handle specific protocols and encodings. Each stream is therefore accessed through the scheme://target syntax, such as the following:

• php://stdin
• file:///path/to/file.ext
• glob://var/www/html/*.php...