<s>
Scsh	B-Language
(	O
a	O
Scheme	B-Language
shell	I-Language
)	O
is	O
computer	O
software	O
,	O
a	O
type	O
of	O
shell	B-Operating_System
for	O
an	O
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
It	O
is	O
a	O
Portable	O
Operating	B-General_Concept
System	I-General_Concept
Interface	O
(	O
POSIX	O
)	O
application	B-Application
programming	I-Application
interface	I-Application
(	O
API	B-Application
)	O
layered	O
on	O
the	O
programming	O
language	O
Scheme	B-Language
,	O
in	O
a	O
manner	O
to	O
make	O
the	O
most	O
of	O
Scheme	B-Language
's	O
ability	O
for	O
scripting	B-Language
.	O
</s>
<s>
Scsh	B-Language
is	O
limited	O
to	O
32-bit	O
platforms	O
but	O
there	O
is	O
a	O
development	O
version	O
against	O
the	O
latest	O
Scheme	B-Language
48	I-Language
that	O
works	O
in	O
64-bit	B-Device
mode	O
.	O
</s>
<s>
It	O
is	O
free	B-License
and	I-License
open-source	I-License
software	I-License
released	O
under	O
the	O
BSD-3-Clause	B-Operating_System
license	O
.	O
</s>
<s>
Scsh	B-Language
includes	O
these	O
notable	O
features	O
:	O
</s>
<s>
Library	B-Library
support	O
for	O
list	O
,	O
character	O
,	O
and	O
string	O
manipulations	O
;	O
</s>
<s>
Regular	B-Language
expressions	I-Language
manipulation	O
support	O
using	O
scheme	B-Language
regular	B-Language
expressions	I-Language
,	O
a	O
domain-specific	B-Language
language	I-Language
(	O
DSL	O
)	O
,	O
or	O
little	B-Language
languages	I-Language
,	O
approach	O
to	O
the	O
abilities	O
;	O
</s>
<s>
High-level	O
support	O
for	O
awk	B-Application
like	O
scripts	O
,	O
integrated	O
into	O
the	O
language	O
as	O
macros	O
;	O
</s>
<s>
Abstractions	O
supporting	O
pseudo	B-Protocol
terminals	I-Protocol
;	O
</s>
<s>
A	O
shell	B-Language
language	I-Language
,	O
modeled	O
using	O
quasi-quotation	O
.	O
</s>
<s>
The	O
reference	O
manual	O
for	O
Scsh	B-Language
includes	O
a	O
spoof	O
Acknowledgments	O
section	O
written	O
by	O
Olin	O
Shivers	O
.	O
</s>
