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#46

September 16th, 2004, 12:29 PM

StanleyGuy

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#44 - How do I make a PHP CRON job run?

Most server hosts these days have CRON control panels and you can setup the time and frequency of how often you want it to run. Usually there is an obvious pull down menu or descrptions of how to set time.

Then there is usually a box where you enter the command itself. On this line you must first enter 'php' then a space then the full path to the script to run on the server. For example:

php /home/mydomain/public_html/script.php

Also, if your php script uses any includes or tried to open any text files for reading or writing you'll need to include the full path those files as above inside your script.php - ie '/home/etc/etc' even if those files reside in the same directory as the php script your initiallly referencing with the cron job.

#47

September 18th, 2004, 07:23 AM

OliverD

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Reducing the number of sql queries

[edit] Posted in the wrong place, sorry. What a bad start

#48

September 24th, 2004, 09:16 PM

Jimmy_Jamal99

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Php development in wrong category

Hey, this php category is in programming languages, while it should be in scripting languages. You probably dont care, I was just making sure you know

#49

September 25th, 2004, 12:52 AM

wannabe

=) wannabe?

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you notice that before HTML programming

#50

September 25th, 2004, 06:59 AM

deltacoder

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Quote:

Originally Posted by Jimmy_Jamal99

Hey, this php category is in programming languages, while it should be in scripting languages. You probably dont care, I was just making sure you know

Enough with the nitpicking.

#51

October 7th, 2004, 10:31 PM

rogs

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dynamic dropdown script missing form_open function

Good clean script.

I copied and pasted the code and got several error messages. Copying in sections and reformating lines cleaned up script.

I don't seem to find the "form_open ()" function per the "print form_open ()" statement. Please provide function or feedback.

Thanks for your valued assistance.

~~~~~~~~~~~~~~

Quote:

Originally Posted by saintp

#41. How do I make a select list/drop down menu autopopulate depending on the value of another select list?

This one must come up three times a day.

Here is real code that I have used to great success; this snippet comes from a system that lets students in some of our chemistry courses do their labs via a PHP app. This snippet is from the administrative-side "edit a lab" script. I've tried to remove all custom functions

PHP Code:


		
			
//************** start dynamic drop-down list magic ***************// 

  print "<script language=\"javascript\"><!--\n"; 

  $classes = mysql_query("SELECT class FROM classes ORDER BY class"); 

  print "var labIDs = new Array(" . mysql_num_rows($classes) . ");\n"; 

  print "var labNames = new Array(" . mysql_num_rows($classes) . ");\n"; 

  while (list($class) = mysql_fetch_array($classes)) { 

     $labs = mysql_query("SELECT DISTINCT labID FROM duedates WHERE class = $class ORDER BY due"); 

     print "labIDs[$class] = new Array(" . (sizeof($labs) + 1) . ");\n"; 

     print "labNames[$class] = new Array(" . (sizeof($labs) + 1) . ");\n"; 

     $i = 1; 

     print "labIDs[$class][0] = 0;\n"; 

     print "labNames[$class][0] = 0;\n"; 

     while (list($lab) = mysql_fetch_array($labs)) { 

        print "labIDs[$class][$i] = '$lab';\n"; 

        print "labNames[$class][" . $i++ . "] = '"; 

        print addslashes(mysql_result(mysql_query("SELECT name FROM labs WHERE class = $class AND labID = $lab"), 1)); 

        print "';\n"; 

     } 

  } 

  print <<<EOJS 

function clean(what) { 

  for (; what.options.length > 1;) { 

     what.options[what.options.length - 1] = null; 

  } 

} 



function updateLabs(which) { 

  with (document.forms[0]) { 

     clean(which); 

     curClass = course.options[course.selectedIndex].value; 

     for (var i = 1; i < labIDs[curClass].length; i++) { 

       which.options[which.options.length] = new Option(labIDs[curClass][i] + ". " + labNames[curClass][i], labIDs[curClass][i]); 

     } 

  } 

} 

//--></script> 

EOJS;  //************** end dynamic drop-down list magic ***************// 



  print form_open(); 

  //replace the old static drop-down tag with a new dynamic one 

  print "Course: <select name=\"course\" onChange=\"javascript: updateLabs(lab);\">\n";

  $classes = mysql_query("SELECT class FROM classes ORDER BY class")

  print "<option value=0 selected>Choose one:</option>\n";

  while (list($class) = mysql_fetch_assoc($classes)) {

    print "<option value=$class>$class</option>\n";

  }

  print "</select><br>\n";

  print "Lab: <select name=\"lab\">\n<option value=0>Choose one\n</select><br>\n"; //will get filled automagically

This script dumps all of the requisite data into JavaScript, and then clears and updates the dynamic select list every time the static one is changed. I've used similar code to do the same thing with one static and two dynamic select lists.

#52

October 8th, 2004, 02:12 AM

deltacoder

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i'm thinking form_open is another function in the chemistry lab app that is not critical for the demonstration at hand.

#53

October 16th, 2004, 01:35 PM

StanleyGuy

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#45 - Why aren't my Session variables staying set?

1. Check to make sure that all pages begin with session_start() and that all the session variables you are trying to set or access are called within $_SESSION[] such as $_SESSION['username']

2. If you are using redirects anywhere on your pages using the header() function with LOCATION then chances are your session variables may get lost along the way. The way to solve this is anywhere you use a header() redirect, on the line prior to it put:

session_write_close();
//then redirect here

This makes sure your session variable updates are written before the redirect takes place.

3. If you've checked all of the above and you're still losing session variables or even worse they're changing on you to different values and you can't figure out why there is a more insidious problem with session vars and register_globals.

Usually you think of register_globals as an easy way to access GET or POST vars without having to parse through the whole $_GET or $_POST array. Well register_globals effects $_SESSION too, and not just for reading variables but for writing them too!!

This is important because if register globals is turned on, and on the first page of your site you set a session var like:

$_SESSION['fruit']="apple";

Then on some other page of your site afterwards you write:

$fruit="banana";

It sets $_SESSION['fruit'] equal to "banana" without you even using the syntax $_SESSION['fruit'] !!!

This sucks because you now need to be very careful not to write to any normal variables that have the same name as a $_SESSION[] variable, because PHP sort of 'aliases' it over to the session var for reading and writing purposes. Took me a lot of hair pulling to realize this, hopefully it saves you from the same.

#54

November 30th, 2004, 11:10 PM

kabhi

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[QUOTE=firepages]#29 Why does my page and/or javascript not work in $browser_type

A - Check ur javascript generated by PHP.Every browser has its DOM specifications.your javascript must be compatible with the DOM of the browser on which you are running ur javascript so that the page don't get rendered.
Use DHTML tags instead of HTML tags in your html page to provide cross browser compatibility so that your pages not get rendered on different browsers.PHP has nothing to do with the page display on the browser.Its only the javascript/html/CSS that decides the layout of your page on different browsers.

check your browser name using navigator.appName and then load ur page according to the browser name/DOM type of the browser.
cheers.....
Abhishek

#55

February 18th, 2005, 09:55 AM

djlosch

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Location: miami

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for sessions...

it took me forever to figure out how exactly they work, but you can have LOTS of code before your session_start(); the only thing is that NONE OF IT CAN OUTPUT ANYTHING TO THE SCREEN. if it does you'll get the cant send headers info. this means you can set cookies and session vars without using javascript redirects etc

#56

June 19th, 2005, 10:37 PM

edman007

Trapped on the forums...help

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#46 - I am changing the settings in my php.ini but the changes are not taking affect

1. You MUST restart the server unless php is running as a CGI for the changes to take affect

2. Check the value of "Configuration File (php.ini) Path" in your phpinfo(); page
if the value is a path to a file (gives the full path to the php.ini, including the php.ini part), then make sure that that is the file that you are editing

if php does not give the php.ini part in the path (ie, it gives the path to a folder) then this means that php searched that folder for a php.ini but could not find one, so it is not using the defaults, if you would like to change the settings put a file named php.ini in that folder and edit that

3. You server may be telling php to set new values
in apache for example, you can change the settings with the "php_flag" config option in either your httpd.conf or a .htaccess, check these files if you are running apache to make sure that they are not overriding the settings in the php.ini

if this is happing then the phpinfo(); page will have differing values for master and local in some places (probably the ones you are having trouble setting)

4. You scripts may be changing the settings
check you scripts for calls to ini_set(), that function can set some (but not all) configuration options from the script

again, if this is happing then the phpinfo(); page will have differing values for master and local in some places (probably the ones you are having trouble setting)

__________________
Feed ME

#57

November 4th, 2005, 01:32 PM

bmitchell@2s4e

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Quote:

Originally Posted by esha

What should I do if I am getting this fatal error:Fatal error: Cannot redeclare <bold>somefunction()</bold> (previously declared in \somewhere\filename.php:line x) in \somewhere\filename.php:line x?

It means you have the same include file in two places.
for example let us say you have a file name index.php

and in index.php:
<php>
include("file1.php");
include("file2.php");
</php>
and then let us say in file1.php:
<php>
include("file2.php");
</php>
then you will get this fatal error. all you need to do is comment out include file2.php inside file1.

As an alternative:
include_once (or require_once)
will only include the file if it hasn't done so already..

#58

November 6th, 2005, 03:52 PM

LinuxPenguin

fork while true;

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