Notes on The MV Shell
This section provides additional information related to interacting with Caché from the MV shell.
The MV shell provides the ability to execute MVBasic commands directly by preceding them with a semicolon. For example,
; A = 2 ; B = 3 ; PRINT "The product is " ; PRINT A*B
will result in 6 being echoed to the terminal window.
The MV shell provides a way to issue ObjectScript commands without having to terminate shell operation. The COS command sends the remainder of its line to Caché for execution. For example, at the MV prompt, the command
COS WRITE "Hello, World", !
will write the expected string to the output device followed by a newline. Since multiple Caché commands may be placed on a line (separated by single blank spaces), a single invocation of COS may execute multiple Caché commands.
The character “[” may be used in place of the “COS”.
Items with a "null" id are only partially accessible from the shell. For TCL-II commands, the following will work:
CT FILENAME '' CT FILENAME ' ' 'SOMEITEMID'
but the following will not:
CT FILENAME 'SOMEITEMID' ''
The null id has to be the first id in the list. In addition,
For CMQL commands, like LIST-ITEM and LIST/SELECT/SORT/REFORMAT, the null item cannot be referenced at all.
For commands that use the active select list, a null item in the list will not be found.
InterSystems discourages users from creating items with a null id and recommends that the only command they use on such items is DELETE.