Linkar Clients 2.1.3

PERSISTENT FUNCTIONS

Exclusively from OOP (OBJECT-ORIENTED PROGRAMMING) and allow the creation of a LinkarClt object that manages all the operations.

After creating the object, it is necessary to Login that, through a Session code; this allows it to make all the desired operations until a call to the Close method is produced or until the session expires because of inactivity. This is defined on its EntryPoint.

They are useful for applications that require user identification, for instance, to log into an ERP session.

DIRECT FUNCTIONS

Used for direct and independent communication with the database.

Its arguments contain the necessary information to identify the user before returning the required information.

Unlike persistent functions, these do not have a Session Code, each call is completely independent of the others and does not have Login or Close functions.

They are used for database access from public websites, for instance online shops.

TEXT FUNCTIONS

This type of function does not need to access the database.

They are executed in the client and their goal is to ease the management of the MV buffers.

They are grouped in the MV Functions and Data Functions chapters.

C AUXILIARY FUNCTIONS

C auxiliary Functions are exclusive for C libraries.

These functions do not access the database.

They are executed in the client and their goal is to allow easier management of other complex C functions.

There are no classes in C, or objects, these functions are used to create encoded strings that emulate other languages.

SYNCHRONOUS CALLS

Executed in the same thread of the main application, so they block the execution of the application until they finish.

For example: The Read function makes a synchronous request, halting main thread code flow until a response is received or until timeout.

ASYNCHRONOUS CALLS

Executed in a new thread, async calls do not block the execution of the application. A return method is required when a call is made (Callback), which is triggered when the operation has completed.

For example: The ReadAsync function does not block. It does not wait for a response.

Be aware of requirements for performing UI operations on the main thread, which is not related to Linkar.

Important

C libraries cannot perform Async operations. Because the libraries for other languages are built around the C library, this implies that async calls cannot be performed with PHP, JavaScript, Python ... even though these languages are themselves async-capable.