# iblock

int iblock (int boardDevice);

## Purpose

Blocks other processes from accessing the specified GPIB-ENET board or device. You can release the lock by calling ibunlock with the same board or device descriptor.

By default, a process returns an ELCK (21) error when it attempts to use a board or device locked by another process. You can cause your process to block instead of returning an error by making the following function call:

ibconfig (boardOrDevice, IbcBlockIfLocked, 1);

There is no timeout on the process that remains in a blocked state.

In general, you should use iblock to gain critical access to a GPIB-ENET board or device when multiple processes might be accessing it at the same time. When the GPIB-ENET is locked, the GPIB driver guarantees that subsequent calls you make to the GPIB-ENET are completed without interruption.

## Parameters

Input
Name | Type | Description
--- | --- | ---
boardDevice | integer | Device descriptor you obtain from OpenDev, ibfind, or ibdev.

## Return Value

Name | Type | Description
--- | --- | ---
status | integer | Indicates whether the function succeeded.

## See Also

ibunlock