Error Handling Terms

Debugging :

A phase of software development where errors are identified and fixed.

Error :

The presence of some element of an operation that does not satisfy the requirements of the operation. An error when encountered causes failure, which in turn raises an exception.

See Also: Exception, Failure, Runtime Error

Error Handling :

The concept of including code in a program so that exceptions to normal operational states that occur during the program execution can be anticipated and dispatched with the least possible detrimental consequences to the use of the program and the data being worked on.

See Also: Exception, Runtime Error

Exception :

An occurrence of an abnormal condition during the execution of an operation. An exception is said to be raised when an operation fails.

See Also: Error, Failure, Runtime Error

Failure :

The inability of an operation to satisfy its purpose. When a failure occurs an exception is raised. Failures are due in large part to errors.

See Also: Error, Exception, Retry, Runtime Error

Recovery :

The process of attempting to handle an exception or runtime error. Generally, recovery consists of three possible actions: terminate processing, retry the failed operation, or resume processing with the next operation. In all cases, the environment of the program must be restored to a stable state.

See Also: Error, Exception, Failure, Retry, Runtime Error

Retry :

After an exception has been raised and the conditions of a failure corrected, an attempt is made to reexecute the failed operation.

Runtime Error :

An error that halts a program while it is executing.

Stub :

A procedure used for debugging purposes that only simulates the intended actions of the real procedure. It may display an indicating message, return a constant value, or do nothing.

Network Terms

Collision :

An attempt by more than one user (typically on a networked, multiuser system) to update a database simultaneously, usually resulting in data corruption. Generally due to poor implementation of the code to support multiuser operations.

See Also: Deadly Embrace, LAN, Local Area Network

Deadly Embrace :

In a multiuser database management system, the result of an unforeseen flaw that has allowed a situation wherein two or more simultaneous operations cannot be completed because each has instigated locks on files or records that the other needs to complete its task.

Exclusive :

In a network, to assure that no other user will write data to a file, it may be opened in an Exclusive mode. Only the user opening the file exclusively may then access it until exclusive use of the file (by closing it, or opening it SHARED) is relinquished.

File Locking :

The process by which a user is guaranteed exclusive access to a database file. The file is only available to the user that applied the lock.

See Also: Record Locking

File Server :

A computer on a network dedicated to providing data storage to other computers (i.e., workstations) for the purpose of sharing information among multiple users. File servers tend to provide other services such as E-Mail service and shared printer support as well.

LAN :

An acronym for Local Area Network. Generally used to describe a system by which microcomputers are connected together to perform such functions as file and peripheral sharing, electronic mail, and centralized backup of data.

Local Area Network :

A system by which microcomputers are connected (via coaxial cable, optical fiber, twisted pair phone wire, or other media), relying on sophisticated operating software to perform such functions as file and peripheral sharing, electronic mail, and centralized backup of data.

See Also : LAN

Record Locking :

The process by which one user obtains exclusive access to a record in a database to prevent another user from attempting to write data to it concurrently. A record lock must be applied prior to writing to a database in use by more than one user.

Retry :

Upon failing to lock a record in a database that is opened in shared mode, retry refers to attempting the write again based upon certain programmatic parameters.

See Also: Error, Exception, Exclusive, Failure, Runtime Error

Shared :

A mode in which a file is opened that allows it to be accessed by more than one user at the same time. The inverse of Exclusive.

Spooler :

See : Print Spooler

Workstation :

A personal computer connected to a network used to run applications and front end processes.

See Also: File Server