<s>
Macintosh	B-Operating_System
Programmer	I-Operating_System
's	I-Operating_System
Workshop	I-Operating_System
(	O
MPW	O
)	O
is	O
a	O
software	B-Application
development	I-Application
environment	I-Application
for	O
the	O
Classic	B-Application
Mac	I-Application
OS	I-Application
operating	B-General_Concept
system	I-General_Concept
,	O
written	O
by	O
Apple	O
Computer	O
.	O
</s>
<s>
For	O
Macintosh	B-Device
developers	O
,	O
it	O
was	O
one	O
of	O
the	O
primary	O
tools	O
for	O
building	O
applications	O
for	O
System	B-Operating_System
7.x	I-Operating_System
and	O
Mac	B-Application
OS	I-Application
8.x	O
and	O
9.x	O
.	O
</s>
<s>
Initially	O
MPW	O
was	O
available	O
for	O
purchase	O
as	O
part	O
of	O
Apple	O
's	O
professional	O
developers	O
program	O
,	O
but	O
Apple	O
made	O
it	O
a	O
free	O
download	O
after	O
it	O
was	O
superseded	O
by	O
CodeWarrior	B-Operating_System
.	O
</s>
<s>
On	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
it	O
was	O
replaced	O
by	O
the	O
Project	B-Operating_System
Builder	I-Operating_System
IDE	B-Application
,	O
which	O
eventually	O
became	O
Xcode	B-Operating_System
.	O
</s>
<s>
MPW	O
provided	O
a	O
command	B-Application
line	I-Application
environment	I-Application
and	O
tools	O
,	O
including	O
68k	B-Device
and	O
PowerPC	B-Architecture
assemblers	B-Language
as	O
well	O
as	O
Pascal	B-Application
,	O
C	B-Language
and	O
C++	B-Language
compilers	B-Language
.	O
</s>
<s>
The	O
shell	O
environment	O
is	O
somewhat	O
similar	O
to	O
Unix	B-Application
shells	I-Application
in	O
design	O
,	O
but	O
is	O
designed	O
around	O
the	O
Macintosh	B-Device
's	O
character	O
set	O
and	O
GUI	B-Application
,	O
replacing	O
the	O
usual	O
terminal	O
environment	O
with	O
a	O
"	O
worksheet	O
"	O
interface	O
,	O
allowing	O
the	O
user	O
to	O
select	O
and	O
run	O
arbitrary	O
sections	O
of	O
a	O
shell	O
script	O
or	O
to	O
redo	O
commands	O
with	O
no	O
retyping	O
.	O
</s>
<s>
In	O
addition	O
,	O
command	B-Application
line	I-Application
tools	I-Application
were	O
commonly	O
provided	O
with	O
a	O
somewhat	O
standardized	O
graphical	B-Application
interface	I-Application
named	O
Commando	O
that	O
provided	O
limited	O
access	O
to	O
the	O
command	B-Application
line	I-Application
capabilities	O
of	O
the	O
program	O
.	O
</s>
<s>
The	O
debuggers	B-Application
were	O
not	O
integrated	O
into	O
MPW	O
like	O
most	O
IDEs	B-Application
of	O
today	O
but	O
the	O
language	B-Language
compilers	I-Language
supported	O
the	O
symbolic	O
debugging	O
information	O
file	O
format	O
used	O
by	O
the	O
debugger	B-Application
.	O
</s>
<s>
MPW	O
supported	O
a	O
source-level	B-Application
debugger	I-Application
called	O
SADE	O
(	O
Symbolic	O
Application	O
Debugging	O
Environment	O
)	O
.	O
</s>
<s>
Apple	O
's	O
compilers	B-Language
had	O
some	O
features	O
that	O
were	O
not	O
common	O
on	O
other	O
platformsfor	O
example	O
,	O
the	O
Pascal	B-Application
compiler	B-Language
was	O
object-oriented	O
,	O
while	O
the	O
C	B-Language
and	O
C++	B-Language
compilers	B-Language
included	O
support	O
for	O
length-prefixed	O
strings	O
(	O
needed	O
for	O
Pascal-oriented	O
APIs	O
)	O
.	O
</s>
<s>
Pascal	B-Application
was	O
Apple	O
's	O
original	O
preferred	O
language	O
for	O
Macintosh	B-Device
software	O
development	O
,	O
and	O
MPW	O
was	O
initially	O
released	O
with	O
only	O
Pascal	B-Application
support	O
.	O
</s>
<s>
A	O
C	B-Language
compiler	B-Language
was	O
released	O
with	O
MPW	O
2.0	O
.	O
</s>
<s>
The	O
MPW	O
C	B-Language
compiler	B-Language
was	O
written	O
under	O
contract	O
for	O
Apple	O
by	O
Greenhills	O
,	O
a	O
Macintosh-variant	O
of	O
the	O
Green	O
Hills	O
C	B-Language
compiler	B-Language
designed	O
specially	O
for	O
Apple	O
and	O
which	O
was	O
similar	O
to	O
the	O
version	O
that	O
was	O
available	O
for	O
the	O
Lisa	O
Workshop	O
.	O
</s>
<s>
In	O
addition	O
,	O
the	O
original	O
MPW	O
C	B-Language
compiler	B-Language
was	O
known	O
for	O
its	O
casual	O
and	O
frequently	O
humorous	O
error	O
messages	O
(	O
"	O
we	O
already	O
did	O
this	O
function	O
"	O
)	O
,	O
as	O
well	O
as	O
occasionally	O
addressing	O
users	O
by	O
name	O
.	O
</s>
<s>
These	O
quirks	O
were	O
not	O
carried	O
on	O
after	O
the	O
PowerPC	B-Architecture
transition	O
,	O
when	O
Apple	O
replaced	O
the	O
originals	O
with	O
compilers	B-Language
written	O
by	O
Symantec	O
.	O
</s>
<s>
Pascal	B-Application
support	O
was	O
no	O
longer	O
provided	O
by	O
the	O
mid-90s	O
due	O
to	O
declining	O
popularity	O
of	O
the	O
language	O
.	O
</s>
<s>
MPW	O
was	O
always	O
targeted	O
to	O
a	O
professional	O
audience	O
and	O
was	O
seldom	O
used	O
by	O
hobbyist	O
developers	O
due	O
to	O
the	O
considerable	O
price	O
for	O
the	O
package	O
;	O
by	O
the	O
time	O
it	O
was	O
made	O
freeware	O
it	O
had	O
long	O
since	O
been	O
superseded	O
by	O
offerings	O
from	O
Symantec	O
and	O
Metrowerks	O
,	O
as	O
well	O
as	O
Apple	O
's	O
own	O
development	B-Application
tools	I-Application
inherited	O
from	O
NeXT	O
and	O
distributed	O
for	O
free	O
with	O
OS	B-Operating_System
X	I-Operating_System
.	O
</s>
<s>
It	O
was	O
also	O
occasionally	O
available	O
as	O
a	O
wrapper	O
environment	O
for	O
third-party	O
compilers	B-Language
,	O
a	O
practice	O
used	O
by	O
both	O
Metrowerks	O
and	O
Absoft	B-Application
among	O
others	O
.	O
</s>
<s>
Apple	O
has	O
officially	O
discontinued	O
further	O
development	O
of	O
MPW	O
and	O
the	O
last	O
version	O
of	O
OS	B-Operating_System
X	I-Operating_System
to	O
run	O
it	O
is	O
10.4	O
'	O
Tiger	O
 '	O
,	O
the	O
last	O
one	O
to	O
support	O
the	O
Classic	O
environment	O
.	O
</s>
<s>
Apple	O
maintained	O
a	O
web	O
site	O
and	O
mailing	O
lists	O
that	O
supported	O
the	O
software	O
long	O
after	O
its	O
discontinuation	O
,	O
but	O
that	O
site	O
now	O
redirects	O
to	O
the	O
Xcode	B-Operating_System
page	O
.	O
</s>
<s>
The	O
MPW	O
Shell	O
featured	O
redirection	B-Device
of	I-Device
output	I-Device
to	O
files	O
,	O
as	O
well	O
as	O
to	O
windows	O
.	O
</s>
<s>
This	O
redirection	B-Device
of	I-Device
output	I-Device
required	O
significant	O
patching	O
out	O
of	O
the	O
file	O
system	O
calls	O
so	O
that	O
tools	O
need	O
not	O
do	O
anything	O
special	O
to	O
inherit	O
this	O
feature	O
:	O
the	O
MPW	O
Shell	O
did	O
all	O
of	O
the	O
work	O
.	O
</s>
<s>
The	O
MPW	O
Shell	O
command	O
language	O
was	O
based	O
on	O
the	O
Unix	O
csh	B-Operating_System
language	O
,	O
but	O
was	O
extended	O
to	O
support	O
the	O
main	O
features	O
of	O
the	O
Macintosh	B-Device
GUI	B-Application
.	O
</s>
<s>
For	O
instance	O
,	O
the	O
classic	B-Application
Mac	I-Application
OS	I-Application
had	O
nothing	O
comparable	O
to	O
Unix	O
fork( )	O
,	O
so	O
MPW	O
tools	O
were	O
effectively	O
called	O
as	O
subroutines	O
of	O
the	O
shell	O
;	O
only	O
one	O
could	O
be	O
running	O
at	O
any	O
one	O
time	O
,	O
and	O
tools	O
could	O
not	O
themselves	O
run	O
other	O
tools	O
.	O
</s>
<s>
These	O
limitations	O
were	O
the	O
inspiration	O
for	O
the	O
MacRelix	O
project	O
,	O
a	O
"	O
Unix-like	O
system	O
"	O
for	O
classic	B-Application
Mac	I-Application
OS	I-Application
.	O
</s>
<s>
Functionally	O
,	O
a	O
worksheet	O
is	O
a	O
cross	O
between	O
a	O
text	B-Application
editor	I-Application
document	O
and	O
an	O
xterm	B-Language
window	O
.	O
</s>
<s>
Unlike	O
an	O
xterm	B-Language
window	O
,	O
an	O
MPW	O
worksheet	O
is	O
always	O
in	O
visual	O
editing	O
mode	O
and	O
can	O
be	O
freely	O
reorganized	O
by	O
its	O
user	O
.	O
</s>
<s>
The	O
commercial	O
BBEdit	B-Operating_System
text	B-Application
editor	I-Application
retains	O
a	O
feature	O
it	O
calls	O
"	O
shell	O
worksheets	O
"	O
on	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
.	O
</s>
<s>
The	O
Emacs	B-Application
text	B-Application
editor	I-Application
provides	O
shell	O
buffers	O
,	O
a	O
similar	O
feature	O
that	O
works	O
across	O
platforms	O
.	O
</s>
<s>
MPW	O
included	O
a	O
version	O
of	O
make	B-Application
.	O
</s>
<s>
Its	O
syntax	O
was	O
conceptually	O
similar	O
to	O
that	O
of	O
Unix	O
make	B-Application
,	O
but	O
used	O
the	O
MacRoman	O
long	O
f	O
character	O
to	O
indicate	O
dependencies	O
.	O
</s>
<s>
More	O
significantly	O
,	O
since	O
the	O
limitations	O
of	O
the	O
shell	O
precluded	O
the	O
make	B-Application
program	O
from	O
running	O
tools	O
itself	O
,	O
it	O
had	O
to	O
work	O
by	O
composing	O
a	O
script	O
of	O
compile/link	O
actions	O
to	O
be	O
run	O
,	O
then	O
delivering	O
that	O
to	O
the	O
shell	O
for	O
execution	O
.	O
</s>
<s>
While	O
this	O
was	O
good	O
enough	O
most	O
of	O
the	O
time	O
,	O
it	O
precluded	O
makefiles	O
that	O
could	O
make	B-Application
on-the-fly	O
decisions	O
based	O
on	O
the	O
results	O
of	O
a	O
previous	O
action	O
.	O
</s>
<s>
Although	O
not	O
implemented	O
as	O
MPW	O
tools	O
,	O
the	O
package	O
also	O
came	O
with	O
several	O
source-level	B-Application
debuggers	I-Application
through	O
its	O
history	O
;	O
SourceBug	O
and	O
SADE	O
(	O
Symbolic	O
Application	O
Debugging	O
Environment	O
)	O
were	O
used	O
on	O
MC680x0	O
systems	O
,	O
while	O
the	O
Power	O
Mac	B-Device
Debugger	B-Application
(	O
known	O
during	O
development	O
as	O
R2Db	O
)	O
provided	O
both	O
local	O
and	O
remote	O
debugging	O
services	O
for	O
PowerPC	B-Architecture
systems	O
,	O
the	O
latter	O
by	O
using	O
a	O
server	O
program	O
known	O
as	O
a	O
"	O
debugger	B-Application
nub	O
"	O
on	O
the	O
computer	O
being	O
debugged	O
.	O
</s>
<s>
MPW	O
included	O
a	O
set	O
of	O
standard	O
C	B-Language
libraries	O
sufficient	O
for	O
developers	O
to	O
build	O
their	O
own	O
MPW	O
tools	O
.	O
</s>
<s>
One	O
point	O
of	O
difficulty	O
was	O
the	O
Mac	B-Application
OS	I-Application
newline	O
convention	O
,	O
which	O
was	O
different	O
from	O
Unix	O
.	O
</s>
<s>
Another	O
was	O
the	O
pathname	B-Application
separator	I-Application
,	O
"	O
:	O
"	O
in	O
Mac	B-Application
OS	I-Application
,	O
but	O
many	O
Unix	O
utilities	O
assumed	O
"	O
/	O
"	O
.	O
</s>
<s>
Many	O
Unix	O
utilities	O
also	O
assumed	O
pathnames	B-Application
would	O
not	O
have	O
embedded	O
spaces	O
,	O
a	O
common	O
practice	O
on	O
Macs	B-Device
.	O
</s>
<s>
For	O
a	O
number	O
of	O
years	O
,	O
the	O
GNU	B-Application
toolchain	I-Application
included	O
portability	O
support	O
for	O
MPW	O
as	O
part	O
of	O
libiberty	B-Application
.	O
</s>
<s>
This	O
was	O
used	O
to	O
support	O
MPW-hosted	O
cross-compilers	O
used	O
by	O
General	O
Magic	O
and	O
several	O
other	O
developers	O
.	O
</s>
<s>
It	O
was	O
going	O
to	O
be	O
called	O
the	O
Macintosh	B-Device
Programmer	O
's	O
System	O
,	O
or	O
MPS	O
.	O
</s>
<s>
'	O
MPS	O
'	O
has	O
always	O
been	O
the	O
creator	B-Operating_System
signature	I-Operating_System
of	O
the	O
MPW	O
Shell	O
as	O
a	O
result	O
of	O
this	O
.	O
</s>
<s>
Since	O
MPW	O
was	O
to	O
be	O
the	O
successor	O
to	O
the	O
Lisa	O
Workshop	O
,	O
they	O
decided	O
to	O
rename	O
it	O
the	O
Macintosh	B-Operating_System
Programmer	I-Operating_System
's	I-Operating_System
Workshop	I-Operating_System
.	O
</s>
<s>
Before	O
the	O
arrival	O
of	O
MPW	O
,	O
Mac	B-Device
applications	I-Device
had	O
to	O
be	O
cross-developed	O
on	O
a	O
Lisa	O
.	O
</s>
<s>
The	O
MPW	O
Pascal	B-Application
compiler	B-Language
is	O
descended	O
from	O
the	O
Lisa	O
Pascal	B-Application
compiler	B-Language
.	O
</s>
<s>
Apple	O
's	O
Larry	O
Tesler	O
worked	O
with	O
Niklaus	O
Wirth	O
to	O
come	O
up	O
with	O
Object	B-Language
Pascal	I-Language
extensions	O
which	O
Ken	O
Doyle	O
incorporated	O
in	O
one	O
of	O
the	O
last	O
versions	O
of	O
the	O
Lisa	O
Pascal	B-Application
compiler	B-Language
.	O
</s>
<s>
This	O
enabled	O
MacApp	B-Operating_System
.	O
</s>
<s>
Early	O
contributors	O
included	O
Rick	O
Meyers	O
(	O
project	O
lead	O
and	O
MPW	O
Shell	O
command	O
interpreter	O
)	O
,	O
Jeff	O
Parrish	O
(	O
MPW	O
Shell	O
editor	O
)	O
,	O
Dan	O
Smith	O
(	O
MPW	O
Shell	O
commands	O
)	O
,	O
Ira	O
Ruben	O
(	O
assembler	B-Language
and	O
many	O
of	O
the	O
tools	O
including	O
Backup	O
,	O
PasMat	O
,	O
and	O
more	O
)	O
,	O
Fred	O
Forsman	O
(	O
Make	B-Application
,	O
Print	O
,	O
SADE	O
,	O
and	O
assembler	B-Language
macro	O
processor	O
)	O
,	O
Al	O
Hoffman	O
(	O
Pascal	B-Application
compiler	B-Language
)	O
Roger	O
Lawrence	O
(	O
Pascal	B-Application
and	O
C	B-Language
compilers	B-Language
,	O
including	O
the	O
error	O
messages	O
)	O
,	O
Ken	O
Friedenbach	O
(	O
linker	O
)	O
,	O
Johan	O
Strandberg	O
(	O
Rez	O
,	O
DeRez	O
,	O
RezDet	O
)	O
,	O
Steve	O
Hartwell	O
(	O
C	B-Language
libraries	O
)	O
,	O
and	O
Dan	O
Allen	O
(	O
MacsBug	O
,	O
editor	O
)	O
.	O
</s>
<s>
A	O
shell	O
memory	B-Error_Name
leak	I-Error_Name
was	O
fixed	O
on	O
October	O
10	O
,	O
1986	O
,	O
and	O
MPW	O
1.0.1	O
was	O
born	O
.	O
</s>
<s>
MPW	O
3.0	O
was	O
done	O
November	O
30	O
,	O
1988	O
and	O
included	O
a	O
completely	O
new	O
C	B-Language
compiler	B-Language
.	O
</s>
<s>
Around	O
the	O
same	O
time	O
,	O
the	O
beta	O
version	O
of	O
the	O
C++	B-Language
compiler	B-Language
as	O
well	O
as	O
MacApp	B-Operating_System
2.0	O
(	O
for	O
Object	B-Language
Pascal	I-Language
)	O
were	O
made	O
available	O
.	O
</s>
<s>
MPW	O
can	O
still	O
be	O
used	O
to	O
develop	O
for	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
,	O
but	O
support	O
is	O
limited	O
to	O
Carbon	B-Operating_System
applications	O
for	O
PowerPC-based	O
computers	O
.	O
</s>
<s>
To	O
develop	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
applications	O
based	O
on	O
other	O
technologies	O
,	O
one	O
must	O
use	O
either	O
Xcode	B-Operating_System
or	O
another	O
OS	O
X-compatible	O
development	O
environment	O
.	O
</s>
<s>
MPW	O
also	O
included	O
a	O
version	B-Architecture
control	I-Architecture
system	I-Architecture
called	O
Projector	O
;	O
this	O
has	O
been	O
superseded	O
by	O
modern	O
version	B-Architecture
control	I-Architecture
systems	I-Architecture
and	O
is	O
no	O
longer	O
supported	O
in	O
Mac	B-Operating_System
OS	I-Operating_System
X	I-Operating_System
.	O
</s>
