mySQL and Linux newbie

dwilson · 17th February 2003, 02:52 AM

Let's say I had my database function type files (i.e., open, close, connect, etc.) in one directory and I had my config file, from which the functions get their data, in another directory, like the parent directory. How would I go about pointing to the other directory? I forgot my old dos days. (i.e., *./somedirectory, ../somedirectory, /somedirectory, etc.?)

Euge · 17th February 2003, 04:05 AM

There are several ways to do this. I'll list them in my personal preferred order from least to most effective:

1) Relative
2) include_path
3) Absolute

Relative: include by using dot notation (../file.inc). There are several disadvantages to using this notation. First, if you move files around, things will break. Second and most important, if you're like me you'll have nested includes. So a single file might include another file which includes another. The problem here is, referencing them relatively is always with respect to the original calling template. For example, if all my includes are in the lib directory, the example below will not work:
original.php -- include('./lib/include1.inc');
include1.inc -- include('./include2.inc');
because even though include1.inc and include2.inc are in the same directory, original.php is one level up, and the nested reference to ./include2.inc will fail. Confused? Don't worry. I suggest you don't use this notation. Its only good for portable apps, in which case you need to structure it such that your entire app will work with this notation.

include_path: In this case you use the include path configured with php. If you run phpinfo() find the value for the directive include_path. I think for our servers its the default value .:/php/includes:/usr/share/php This means for includes it will look first in the current directory of the executing template (.), the /php/includes directory, then the /usr/share/php directory. Obviously, we don't have access to these directories, but luckily we can modify the directive in our .htaccess file. So for the above example to work, you can specify /home/virtual/siteXX/fst/var/www/html/lib as your include_path and reference like this:
original.php -- include('include1.inc');
include1.inc -- include('include2.inc');
or if you specify /home/virtual/siteXX/fst/var/www/html as your include path:
original.php -- include('lib/include1.inc');
include1.inc -- include('lib/include2.inc')
To change the directive, add the following in your .htaccess file:

Code:

php_value include_path '/home/virtual/siteXX/fst/path/you/can/access'

This is not my preferred method because if I switch hosts, I'm not guaranteed .htaccess permissions, so its not as portable.

Absolute: This is the method I use and is most portable. You begin your include path with "/" and give the absolute path to the file relative to the server. But you don't want to hard code your server path. So do this:

Code:

include($_SERVER[&quot;DOCUMENT_ROOT&quot;] . 'path relative to DocRoot');

So for the original example:
original.php -- include($_SERVER["DOCUMENT_ROOT"] . 'lib/include1.inc');
include1.inc -- include($_SERVER["DOCUMENT_ROOT"] . 'lib/include2.inc');

Man am I really verbose. Hope this helps.

dwilson · 17th February 2003, 04:37 AM

Dang, I forgot about $_server!!! I just used that in a mailing script! I tried the first two and they didn't work but the absolute method will be what I need since later it will be on multiple servers. Thanks!

dwilson · 17th February 2003, 04:02 PM

By golly that worked. Thanks man!

UH-Matt · 17th February 2003, 04:06 PM

LOL

Everytime you get a problem you sound SHOCKED when it gets solved... Scripting is designed to work, not everything just breaks and stays broken

dwilson · 17th February 2003, 04:26 PM

I just get excited that I can move on.

dwilson · 17th February 2003, 04:30 PM

I do have another problem though. I am running out of resources or at least that is the error. I am trying to do my includes in one file and require that file when I need to. I have read that the error that I receive is either due to inappropriate access to a file or resources too ow in the php.ini file. Should I just include the path when needed instead of having a common module for includes? or maybe I can insert some code in the includes.php file to check whether I need certain paths?

Here is the error:

Fatal error: Allowed memory size of 8388608 bytes exhausted (tried to allocate 3840 bytes) in /home/virtual/site9/fst/var/www/html/weusa_portal/includes/includes.php on line 2

UH-Matt · 17th February 2003, 04:32 PM

This error does not always mean an actual resource problem. I would double check through the script - the server is in no way struggling

dwilson · 17th February 2003, 04:39 PM

Wierd. All I am doing is:

(The calling script)

Code:

require ($_SERVER[&quot;DOCUMENT_ROOT&quot;] . '/somedir/someotherdir/includes.php');

(the includes.php)

Code:

include ($_SERVER[&quot;DOCUMENT_ROOT&quot;] . '/somedir/someotherdir2/config.php');
include ($_SERVER[&quot;DOCUMENT_ROOT&quot;] . '/somedir/someotherdir2/mysql_connect.php');

It worked when I did the includes in the script that used those paths. I would really like to have a global include so that I will have access to everything I need up front. I suppose that this isn't very efficent anyway since this project could grow in size pretty quickly once I get the newbie stuff out of the way.

UH-Matt · 17th February 2003, 04:43 PM

Just place a config.php somewhere and include it at the top of your scripts, thats how most PHP scripts do it (i think).. no need for document root etc..

dwilson · 17th February 2003, 04:44 PM

Ok. Thanks. (see I didn't get all excited that time. lol) :-X

UH-Matt · 17th February 2003, 04:45 PM

Download a basic PHP/MySQL script and examine it. You can often reuse a lot of perfectly good code.

dwilson · 17th February 2003, 04:48 PM

Yeah but I want to do everything from scratch so that I understand what's going on. Someone could write a script giving away all my site details and I would never know if I didn't know PHP.

I think I found the problem (described above) to be "programmer to keyboard interface." It was really dumb. I had the calling module listed in the include. Oops. I removed it and it works. I will go with your suggestion above (about the config at top of scripts).

UH-Matt · 17th February 2003, 04:50 PM

I didnt mean copy a script, I meant to look at its structure and how the author calls / includes various things.

Get an idea of a good "style" of coding PHP then make something original of your own.

evo4ever · 18th February 2003, 09:12 PM

You don't really need to express $_SERVER['DOCUMENT_ROOT']. document root is a predefined var. you can just use $DOCUMENT_ROOT. Just saves some typing.

[edit]
If you dont want to explicitly type the path of the file you want to include. you can do this:

Code:

$dir = $DOCUMENT_ROOT.strrev(strstr(strrev($PHP_SELF),&quot;/&quot;));

and then:

Code:

include($dir.&quot;filename.php&quot;);

Just make sure its in the same folder as the calling script.
[/edit]

Euge · 18th February 2003, 11:44 PM

Since newer versions of php are defaulting register_globals to off, it is safer to explicitly use the super global _SERVER

dwilson · 19th February 2003, 12:45 AM

Yup that's what i'm doing. If global variables were off would I be able to use "../filname.php" or would it not see that with the globals turned off? I am assuming not,

Euge · 19th February 2003, 01:21 AM

Relative references in your includes would still work.

with register_globals on, php makes assumptions on variables. So it allows you to specify $DOCUMENT_ROOT and it would look for a variable with this name in several namespaces before it assumes it is not set. This is a security flaw.

Newer versions are defaulting register_globals to off, so you have to explicity reference get, post, cookie, server, and environment variables otherwise it will assume the variable hasn't been defined.

evo4ever · 20th February 2003, 12:55 AM

Which is a shame becuase ive been working with reg globs=on since early php3. I agree with you though euge, using the super globs is safer to say the least. Ill just have to get used to the idea that reg globs will be defaulted to off in the very near future.