SYSHANDLE

Top  Previous  Next

The SYSHANDLE datatype is an abstract context-specific unique identifier that is used to safely reference and access system resource such as components in the GUI interface.
The SYSHANDLE is an opaque and general handle type in contrast to context specific handles offered by the SEMAPHORE, CHANNEL, MUTEX and FILE datatypes.

 

A SYSHANDLE has the following attributes:
 

Occupies 4 bytes of storage.

Is only assignment compatible with itself.

Comparison operators are limited to the equal(=) or not-equal(<>) operators.

Type cast is only possible to BOOL where only a valid handle yields TRUE.