PHP is a powerful open source server-sided scripting language that can be used on a wide variety of operating systems and webservers, including Apache on UNIX and IIS on Windows.
PHP contains numerous extensions which enable you to dynamically create images and flash files, parse xml, connect to remote servers using pop, imap, ftp, http and raw sockets, natively access many database servers including PostgreSql, MySQL and Microsoft SQL Server, compress and decompress files, lookup domain names and and much more.
PHP has an excellent manual and online documentation which covers every function for every extension available.
There are several PHP "magic constants" (or "magical contants") which can be useful for a variety of reasons. These magic constants aren’t actually constants at all, but effectively behave like them, although the values change depending on the context.
I run a number of web servers with PHP and MySQL and have a PHP command line script that runs on a daily basis to back up MySQL databases using the mysqldump command. It would be possible to do this using a simple bash script as well, and I know I used to use a bash script in the past but for some reason switched it to PHP at some stage.
It is possible to trigger an error in PHP. This can be useful for debugging purposes, or if there is some condition which occurs in your PHP script which requires a PHP notice, warning or full error which causes the script to halt execution, and which would not be generated by PHP itself.
PHP has a really useful date() function for formatting dates from timestamps. When used in conjunction with strtotime() you can do some really quick and easy manipulation and formatting of dates.
The strtotime() function in PHP allows you to convert English text date time strings into UNIX timestamps. It is useful for converting database datetime strings into UNIX timestamps and also creating dates into the future or past based on the current time or relative to a date and time in the future or the past. This post looks at some examples of doing this.
The end of daylight savings in New Zealand has been changed from Sunday March 16th (today) to Sunday April 6th. Last week I looked out how to check the daylight savings dates will be applied correctly on Linux, but now that it’s actually the day itself it turns out that while the operating system is using the correct date, PHP is not due to PHP5 maintainin its own internal timezone database. This post looks at how to temporarily correct the solution until it’s fixed in the distro’s PHP builds.