Desktop Manager Routines

All low-level desktop manager routines exchange parameters with your

application through a parameter block. When calling a low-level routine, you

pass a pointer to the parameter block.

Three Desktop Manager functions-namely, PBDTGetPath,

PBDTOpenInform, and PBDTCloseDown-run synchronously only. All

other Desktop Manager routines can run either asynchronously or

synchronously. There are three versions of each of these routines. The first

version takes two parameters: a pointer to the parameter block, and a Boolean

value that determines whether the routine is run asynchronously (TRUE) or

synchronously (FALSE). Here, for example, is the first version of a routine

that retrieves the user's comment stored for a file or a directory:

OSErr PBDTGetComment (DTPBPtr paramBlock, Boolean async);

The second version does not take a second parameter; instead, it adds the

suffix "Async" to the name of the routine:

OSErr PBDTGetCommentAsync (DTPBPtr paramBlock);

Similarly, the third version of the routine does not take a second parameter;

instead, it adds the suffix "Sync" to the name of the routine:

All Desktop Manager routines that have separate synchronous and

asynchronous versions are documented using the first version only. Note,

however, that the second and third versions of these routines do not use the

glue code that the first versions use and are therefore more efficient.

Referenced by (6):