Error Handling Scripting
The JANOS PHP implementation compiles script to bytecode. After a reboot any
PHP source file will be compiled when referenced. The compiled bytecode will
be executed to render the page. The compiled code will be retained until the
source file or any included files are modified or until the JNIOR is rebooted.
Subsequent page references use only the cached compiled code. The bytecode
contained therein executes much more efficiently. Pages render faster and
Errors during the compilation phase are reported in three places. When an
error is encountered an error page is rendered and displayed in the browser.
This will define the error, display the faulty source line, and indicate
the error with a pointer. The same information is appended to the php.log
file in the file system root. An error message is also appended to the
system log jniorsys.log . Typically these are Syntax Errors but missing
parentheses or semicolons and numerous other conditions will be
specifically called out. This greatly enhances the debugging experience.
The following errors are reported:
There is something wrong with the program syntax. The compiler was
expecting something in the PHP source that it did not find.
Undefined Function Reference
You have referenced a function but it has not been defined. The first
use of the missing function will be displayed.
There appears to be a missing semicolon. All statements need to be
terminated with a semicolon. Additionally the semicolon should be
properly used in the FOR statement syntax.
A break statement appears outside of a FOREACH, WHILE, DO-WHILE or
A continue statement appears outside of a FOREACH, WHILE, DO-WHILE
or SWITCH structure.
Either an open or close parenthesis is missing.
Unusable Function Name
Reserved words or built-in function names cannot be used in the definition
of user functions. You cannot override existing functions.
Function Name In Use
JANOS does not allow you to redefine a function. Standard PHP
implementations may allow this. If there is a valid application for
this behavior then this can be reported as a bug. INTEG may then opt to
eliminate this restriction.
Illegal File Specification
A file path or name includes an illegal character.
File Does Not Exist
You attempted to include a file that cannot be located. The include
statement presently requires an absolute file path. If you have an
application that requires the use of a relative path or to specify a
file location relative the the WebServer path, report this as a bug.
INTEG may expand the functionality here.
At runtime, when compiled bytecode is executed, certain runtime errors
may occur. Since a page is likely partially rendered before the error
occurs it will appear to stall. The runtime error will be reported in two
places. First and error message will be appended to the system log
jniorsys.log . Secondly the same error message will be added to the php.log
file in the file system root. In addition, the compiler is asked to locate
the related line of source code. This is displayed in the php.log file as
well. In this case the pointer indicates the rough area where execution
The following runtime errors may be reported:
This indicates a PHP logic fault. If this occurs and the related PHP
code appears to be normal then it should be reported as a bug. It
indicates that the expected results of expressions or functions are
missing. Normal PHP would not normally cause this to occur.
This will occur if a PHP operator has been used that has not been
implemented. The JANOS implementation is a subset of standard PHP and
not all operations have been implemented. This error should be extremely
rare. But if you do attempt to use an operation that might be defined
in the table of precedence but not logically implemented you will get
this error. There should be a simple work-around. You may report this
as a bug. INTEG would promptly address the issue.
Not An Array
This runtime error will occur if you attempt to reference a non-array
variable using array syntax. This would be the result of an issue in
the PHP source. If the program is proper and the statement would have
performed in some acceptable way under standard PHP, you may report
this as a bug.
This indicates a compiler failure and should be reported as a bug. This
is a good indication that system integrity has been lost. It should not