In-depth explanation: socket Communication in php

In-depth explanation: socket Communication in php
1. Common Errors in php

1. Syntax Error
* 1). Write less semicolons
* 2 ).. .....

2. Environment Error
* 1). php configuration waiting

3. logical error
* 1) to use an equal sign, two equal signs are used in the result.

2. defined error types

Error name	Error description
E_ALL	All errors and reports
E_ERROR	Fatal runtime error. Script Execution is
E_WARBING	Run-Time Warning (non-fatal), script execution will not be paused
E_PARSE	Parsing error during compilation
E_NOTICE	Runtime reminder
E_STRICT	Start php's code modification suggestions to ensure the best code interoperability and forward compatibility
E_DEPRECATED	Runtime notification. After startup, a warning will be given to code that may not work properly in future versions.
E_CORE_ERROR	Fatal error occurred during php startup Initialization
E_CORE_WARNING	Warning error (non-fatal) during php startup Initialization)
E_COMPILE_ERROR	Fatal errors during compilation
E_COMILE_WARNING	Compile-time warning (non-fatal error)
E_USER_ERROR	Error message generated by the user
E_USER_WARNING	User-generated warning message
E_USER_NOTICE	User-generated reminder message
E_USER_DEPRECATED	User-generated warning information, similar to E_DEPRECATED,trigger_errorFunction generation
E_RECOVERABLE_ERROR	A captured error indicates that a very dangerous error may occur, but the PHP engine is not unstable yet. If the error is not captured by the custom handle (seeset_error_handler()), And the script stops running.

3. error levels in php

1.Deprecated (not recommended | outdated)Error
* 1 ).Lowest-level errorsFor exampleeregFunction, mysql_escape_string
* 2 ).Deprecated: mysql_escape_string(): This function is deprecated; use mysql_real_escape_string() instead.

2.NoticeNotification-Level Error
* 1). Access undefined Variables
* 2) when accessing the array, $ arr ["name"]; The program first queries the constant name. If not found, the program treats the name as a string.

3.WarningWarning-Level Error
* 1) the number of parameters is incorrect.
* 2) the parameter type is incorrect.

4.Fatal errorFatal errors(Terminate the program to continue execution)
* 1). Call undefined Functions
* 2) the parameter type is incorrect.

5.parse errorSyntax Parsing Error
* 1). The check phase fails, and no other errors will be seen, because it is not yet there,The program has not been resolved successfully.

6.E_USER _ related errors
* 1). The check phase fails, and no other errors will be seen, because it is not yet there,The program has not been resolved successfully.

4. Error-related options in the php configuration file

Option	Description
Error_reporting	Set the error report level
Display_error	Show error?
Log_errors	Set whether to record the generated error information to the log or error_log
Error_log	Set an error log storage file
Log_errors_max_len	Set the maximum number of log_errors bytes
Ignore_repeated_errors	Ignore duplicate error messages?
Ignore_repeated_source	Ignore duplicate message sources
Track_errors	If this option is enabled, the last error will always be saved in$php_errormsgMedium

5. How to set the error level

1. Modify the error_reporting value in the configuration file.

2. PassError_reporting FunctionSet
* 1. error_reporting (0); no error is displayed, except for E_PARSE
* 2. error_reporting (-1) | error_reporting (E_ALL) show all errors

3. Use ini_set ('error _ report', 0) to set

6. Suppress error output symbols @

1.@Settype ()

7. PHP errors returned by trigger_error

The function of triggering an error is not only limited to the php parser, but also trigger_error()Function trigger error. Trigger_error ('error information', custom error, for example: (E_USER_NOTICE) trigger_error ('custom error information', E_USER_NOTICE); this function does not interrupt the program to continue execution.