Under APLX, you can access, at one time, up to ten user-specified libraries (0-9, regardless of the
⎕IO setting). (Note: Library 10 is always mapped to the library containing utility and demonstration workspaces supplied with APLX.) You can also specify full pathnames in system commands such as
)LOAD, in order to access directories which are not allocated to library numbers.
⎕MOUNT allows you to read or alter the mapping between APLX Library Numbers and directories on the system. Library numbers are used by System Commands such as
)SAVE, as well as by the APLX file systems.
⎕MOUNT with an empty vector character right argument will return the current mapping. This will be a matrix with 10 rows and up to 260 columns, corresponding to library numbers 0 to 9. For example, under MacOS you might have:
MacHD:apl:ws: Logical Unit 0
MacHD:users:jim: Logical Unit 1
Logical Unit 2 (Blank)
Alteration of the table:
You can change the mapping of library numbers to directories by using
⎕MOUNT with a vector or matrix text right argument.
VARIABLE is a 10 row matrix, all of
⎕MOUNT changes. Otherwise as much of
⎕MOUNT as is affected, changes. For example, if
VARIABLE has 4 rows, it will alter the top four rows (libraries 0 to 3) of
⎕MOUNT. A vector right argument alters the top row, as does a scalar right argument.
The result returned is the new setting of
Note that you should include the trailing directory separator in directory specifications. This is
/ for AIX and Linux systems,
\ for Windows systems, and : for MacOS.
A blank row means the current default directory (ie the directory you were in when you started APLX).
Note that you can specify the
⎕MOUNT table to be used when APL starts up in the future. To do this, choose the Preferences item in the Tools menu.
Special considerations for Client-Server implementations of APLX
In Client-Server implementations of APLX, the front-end which implements the user-interface (the "Client") runs on one machine, and the APLX interpreter itself (the "Server") can run on a different machine.
In such systems, you can specify whether the directory to be associated with a line of
⎕MOUNT is on the Client or the Server machine. You do this by preceding the path name with either an Up Arrow
↑ to indicate that the directory is on the Client, or a Down Arrow
↓ to indicate that it is on the Server. (If you do not specify, the default is that the access takes place on the Client.)