Configuring Apache to use a .htaccess file

Just a good step by step on how to configure Apache to use a .htaccess file. I rarely ever use this method except in testing so I always forget.

First, get your web administrator to enable your use of .htaccess files. This requires a stanza in ServerRoot/conf/access.conf like this:

AllowOverride AuthConfig

where /home/webber is replaced by your home directory. Without this, the usual default is AllowOverride None, which means that .htaccess files are ignored. The above stanza allows .htaccess control in all subdirectories of the specified Directory.

Set up a reasonably secure directory for the password (and optionally the group) files. This directory should not be in the web document tree! If it is, someone who can learn or guess the URL of the password file can fetch it and try to crack the passwords. (This refers to visitors from elsewhere on the Internet. There is no simple way to prevent users with accounts on the web server host itself from snooping in the password file, so we will have to settle for security by obscurity and trust them not to try too hard.)
Let us name this directory http-etc by analogy to the Unix /etc directory where the system passwd and group files reside. Place it in your home directory (not in public_html) so that it is outside URL space. Give it permission 701 = rwx-----x meaning you the owner can do anything, and the web server, running as the ordinary user apache, can access the directory but cannot list it (so it must know the file names in advance).1

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Backup files with tar

I don't remember where I got this article from but it is full of some good information

TAR is the Unix Tape ARchive utility. It can be used to either store data on a streaming tape device like a DAT drive, or store files in what is commonly called a tarball file- somewhat like a pkzip file, only compression is optional.

[The basics]

In these examples, I will use the following file structure: a top level directory called DIR1 containing the files picture.jpg, document.doc and database.db.


[Creating a tarball]

If we were in the directory DIR1 and wanted to backup all the files to a tarball called backup.tar, we could issue this command:

$ tar cvf backup.tar .
tar: backup.tar is the archive; not dumped

c=create (an archive)
v=verbose (just because)
f=filename (the name of our tarball)
.=current directory (what's going to be backed up)

Also worth mentioning is that by default tar is recursive- meaning it will back up all files and subdirectories recursively unless you otherwise specify with the n flag (non-recursive)

[Displaying the Contents of a Tarball]

The current directory will now contain a file called backup.tar. To display the contents of the tarball file, we could issue this command:

$ tar tvf backup.tar
drwxr-xr-x root/gci 0 Jun 29 10:10 ./
-rw-r--r-- root/gci 1 Jun 29 10:10 picture.jpg
-rw-r--r-- root/gci 1 Jun 29 10:10 document.doc
-rw-r--r-- root/gci 1 Jun 29 10:10 databse.db
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Learning to Use Regular Expressions by Example

Dario F. Gomes

This site I'm working on relies heavily on user input through forms, and all that data needs to be checked before being sent a database. I knew PHP3's regular expression functions should solve my problem, but I didn't know how to form the regular expressions in the first place. What I needed were some sample strings--obviously the first places I looked were the PHP3 manual and the POSIX 1002.3 specification, but they don't help much in the way of exemplifying.
Adding to that, I had a really hard time finding good literature on the Web about the subject. I eventually got to know how to do it, mostly through experimenting, and seeing there wasn't much to it, I decided to write down this straight-out introduction to the syntax and a step-by-step on building regular expressions to validate money and e-mail address strings. I just hope it manages to clear the fog around the subject for all you fellow programmers.

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