MICROSOFT
SYSTEMS
JOURNAL
CMD.EXE—OS/2 Command Processor
The Or operator performs one of two commands depending on the success or
failure of the first command given. For example, in the following
more < document.txt II more < document.doc
more will either output the contents of document.txt and then exit, or, if
document.txt doesn't exist, will output the contents of document.doc.
The Command Separator allows more than one command to be typed on a
command line. For example,
dir a:\*.* > temp & dir b:\*.* » temp
places the directory listing of the root directory of a: in a file called temp
(which is either overwritten if it exists or is created if it doesn't exist) and then
immediately executes the next command, which appends the contents of the
root directory of b: to temp.
BATCH FILE ENHANCEMENTS
OS/2 supports all of the old batch file commands and adds four new ones.
They are
CALL
EXTPROC
SETLOCAL
ENDLOCAL
The Call command finally provides a means for users to chain together batch
files so that when a called batch file ends it returns control to the calling batch
file.
Extproc allows a user to run batch files designed for command processors
other than CMD.EXE. The command is issued as the first line of the batch file
and defines the alternate command processor.
Setlocal allows the user to define local drive, directory and environment
variables for the current batch file. When the command is issued it saves the
existing drive, directory and environment information and replaces it with the
user specified information.
In conjunction with the setlocal command, the endlocal command restores
the drive, directory and environment information previously saved through
setlocal, and allows additional setlocal calls.
If a setlocal call is issued and the batch file issuing the setlocal call
terminates without issuing an endlocal call, the operating system restores the
original drive, directory and environment information, insuring that the state
previously known to CMD.EXE still exists.
ready been anticipated and re
solved; Microsoft guarantees to
support a subset of the API
function set that will execute
in every available mode of the
two operating environments.
Dubbed the Family Applica
tion Programming Interface
(FAPI), this set of 91 func
tions—25 of them are some
what restricted—will permit
programs to execute under MSDOS 3.3, within the compati
bility mode of MS OS/2, and
as an actual, although limited,
MS OS/2 application (see Fig
ure 6).
API/FAPI represents a
unique opportunity for software
developers to create applica
tions that can deal with current
limitations while incorporating
future advances, thus providing
users to run state-of-the-art ap
plications on older machines.
Software Assistance
By August, Microsoft plans
to release a Software Develop
ment Kit (SDK) that will
contain the full specifications
of MS OS/2—as well as a betarelease version of the operating
system kernel. The toolkit will
come with C Version 4.5,
MASM Version 4.5, and the
CodeView debugger.
The new compiler and assem
bler will be able to generate
code to be used with the new
Microsoft Dynamic Linker.
The linker will allow code to
be linked with FAR calls, cre
ating external references to
various libraries. These exter
nal references eliminate the
need to link library routines
into each object (or load) mod
ule. The Dynamic Link Editor
services program needs by load
ing library routines only when
necessary.
The LAN Manager
The LAN Manager will play
an important role in the MS
OS/2 environment and can be
fully integrated into MS OS/2.
It promises an exciting new
applications environment in
which different applications,
such as spreadsheets, word pro
cessors, and database systems,
will be able to communicate
with each other not only appli
cation-to-application (e.g.,
spreadsheet to word processor)
within one processor, but also
among processors connected to
pcjs.org
MAY 1987