Have you ever wanted to access a home computer or server but you didn’t know your IP address? That’s probably because your IP address is dynamic and changes periodically. So how do you find out what your IP address is? If you’re on your home network, then it’s easy by using any number of websites whose sole purpose is to tell you what your IP address is, for example www.whatsmyip.org. But what if you’re away from home and your IP address changes? Again, there are services to help you with this, but in this article, I’m going to show you how to easily setup your own service.
Category Archives: Programming
Regular Expression Cheatsheet
Here’s a quick cheatsheet of the metacharacters used in regular expressions.
| Metacharacter | Name | Matches |
|---|---|---|
| . | dot | any one character |
| [ ... ] | character class | any character listed |
| [^...] | negated character class | any character not listed |
| ^ | caret | the position at the start of the line |
| $ | dollar | the position at the end of the line |
| \< | backslash less-than | the position at the start of the word |
| \> | backslash greater-than | the position at the end of the word |
| | | or, bar | matches either expression it separates |
| ( ... ) | parentheses | used to limit scope of | |
| ? | question mark | one allowed; none required ("one optional") |
| * | asterisk | unlimited allowed; none required ("any amount OK") |
| + | plus | unlimited allowed; one required ("at least one") |
| \1, \2, ... | back reference | matches text previously matched within first, second, etc., set of parentheses |
| \ | backslash | escape a metacharacter to match literally |
| { ... } | braces | Interval; counting quantifier; specify number of matches |