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Linux getsockopt SO_ERROR values (errno.h)

Created by voodoo on August 03, 2012 08:42:38 Last update: August 03, 2012 09:31:25

The C function getsockopt lets you get the error codes with the option SO_ERROR . The possible error numbers are defined in the global errno.h . The relevant values are:

#define	ETIMEDOUT	110	/* Connection timed out */
 ...

But here's the whole list on my Linux system ( /usr/include/asm-generic/errno.h ):

#ifndef _ASM_GENERIC_ERRNO_H
 
 #define _ASM_GENER...

jQuery validate select required example

Created by James on February 02, 2012 09:20:22 Last update: February 02, 2012 09:20:22

This example came from the jQuery validation documentation. The required rule can be used to validate a required selection box when you set the value of the first option to empty.

<!DOCTYPE HTML> 
 
 <html>
 
 <head>
 
     <scrip...

The error message is the title since no error message is specified. A more fully defined validation check would look like this:

$('#my-form').validate({
 
 		errorElement: "p",
 ...

PHP error level constants

Created by jinx on May 03, 2011 08:56:55 Last update: May 03, 2011 08:57:54

These error level constants are defined in PHP : Constant Value Description E_ERROR 1 Fatal run-time errors. Execution of the script is halted. E_WARNING 2 (1<<1) Run-time warnings (non-fatal errors). Execution of the script is not halted. E_PARSE 4 (1<<2) Compile-time parse errors. Parse errors should only be generated by the parser. E_NOTICE 8 (1<<3) Notices. Indicate that the script encountered something that could indicate an error, but could also happen in the normal course of running a script. E_CORE_ERROR 16 (1<<4) Fatal errors that occur during PHP's initial startup. This is like an E_ERROR, except it is generated by the core of PHP. E_CORE_WARNING 32 (1<<5) Warnings (non-fatal errors) that occur during PHP's initial startup. This is like an E_WARNING, except it is generated...

PHP try catch finally

Created by jinx on May 02, 2011 20:48:49 Last update: May 02, 2011 20:58:01

A PHP try catch block looks like this:

<?php
 
 try {
 
     throw new MyException('foo!'...

Normally, no exceptions are thrown from internal function errors. For example:

<?php
 
 $a = 1;
 
 $b = 0;
 
 try {
 
     $v = $...

The division by zero error is never caught as an exception. However , you can translate errors into exceptions with an error handler and ErrorException :

<?php
 
 function exception_error_handler($errno, ...

which prints: Exception: exception 'ErrorException' with message... PHP does not support finally clause.

PHP errors not displaying

Created by jinx on April 10, 2011 21:15:46 Last update: April 10, 2011 21:23:04

When developing in PHP, it's frustrating to have errors in the code but no error message displays. According to the PHP manual, the display_errors setting controls whether errors are displayed. You can either change it in php.ini : ; This directive controls whether or not and where... or set it in your code:

<?php
 
 ini_set('display_errors', 'On');
 
 fsdlf...

But when you have syntax errors in your code, the ini_set function may not even get a chance to execute. So the only reliable way is to set it in php.ini :

<?php
 
 // nothing gets displayed when display_er...