Scsh (a ''Scheme shell'') is computer

software Software consists of computer programs that instruct the Execution (computing), execution of a computer. Software also includes design documents and specifications. The history of software is closely tied to the development of digital comput ...

, a type of

shell Shell may refer to: Architecture and design * Shell (structure), a thin structure ** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses Science Biology * Seashell, a hard outer layer of a marine ani ...

for an

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

. It is a Portable Operating System Interface (

POSIX The Portable Operating System Interface (POSIX; ) is a family of standards specified by the IEEE Computer Society for maintaining compatibility between operating systems. POSIX defines application programming interfaces (APIs), along with comm ...

)

application programming interface An application programming interface (API) is a connection between computers or between computer programs. It is a type of software Interface (computing), interface, offering a service to other pieces of software. A document or standard that des ...

(API) layered on the programming language Scheme, in a manner to make the most of Scheme's ability for scripting. Scsh is limited to

32-bit In computer architecture, 32-bit computing refers to computer systems with a processor, memory, and other major system components that operate on data in a maximum of 32- bit units. Compared to smaller bit widths, 32-bit computers can perform la ...

platforms but there is a development version against the latest Scheme 48 that works in

64-bit In computer architecture, 64-bit integers, memory addresses, or other data units are those that are 64 bits wide. Also, 64-bit central processing units (CPU) and arithmetic logic units (ALU) are those that are based on processor registers, a ...

mode. It is

free and open-source software Free and open-source software (FOSS) is software available under a license that grants users the right to use, modify, and distribute the software modified or not to everyone free of charge. FOSS is an inclusive umbrella term encompassing free ...

released under the BSD-3-Clause license.

Features

Scsh includes these notable features: *

Library A library is a collection of Book, books, and possibly other Document, materials and Media (communication), media, that is accessible for use by its members and members of allied institutions. Libraries provide physical (hard copies) or electron ...

support for list, character, and

string String or strings may refer to: *String (structure), a long flexible structure made from threads twisted together, which is used to tie, bind, or hang other objects Arts, entertainment, and media Films * ''Strings'' (1991 film), a Canadian anim ...

manipulations; *

Regular expression A regular expression (shortened as regex or regexp), sometimes referred to as rational expression, is a sequence of characters that specifies a match pattern in text. Usually such patterns are used by string-searching algorithms for "find" ...

s manipulation support using ''scheme regular expressions'', a

domain-specific language A domain-specific language (DSL) is a computer language specialized to a particular application domain. This is in contrast to a general-purpose language (GPL), which is broadly applicable across domains. There are a wide variety of DSLs, ranging ...

(DSL), or little languages, approach to the abilities; * Strong networking support; * High-level support for awk like scripts, integrated into the language as macros; * Abstractions supporting

pseudo terminal In some operating systems, including Unix-like systems, a pseudoterminal, pseudotty, or PTY is a pair of pseudo-device endpoints (files) which establish an asynchronous, Duplex (telecommunications), bidirectional communication (IPC socket, IPC) c ...

s; * A

language, modeled using quasi-quotation.

Example

* Print a list of all the executables available in the current

PATH A path is a route for physical travel – see Trail. Path or PATH may also refer to: Physical paths of different types * Bicycle path * Bridle path, used by people on horseback * Course (navigation), the intended path of a vehicle * Desir ...

to the

standard output Standard may refer to: Symbols * Colours, standards and guidons, kinds of military signs * Standard (emblem), a type of a large symbol or emblem used for identification Norms, conventions or requirements * Standard (metrology), an object t ...

: #!/usr/local/bin/scsh -s !# (define (executables dir) (with-cwd dir (filter file-executable? (directory-files dir #t)))) (define (writeln x) (display x) (newline)) (for-each writeln (append-map executables ((infix-splitter ":") (getenv "PATH"))))

"Acknowledgments"

The reference manual for Scsh includes a spoof Acknowledgments section written by Olin Shivers. It starts: :''Who should I thank? My so-called "colleagues", who laugh at me behind my back, all the while becoming famous on my work? My worthless graduate students, whose computer skills appear to be limited to downloading bitmaps off of netnews? My parents, who are still waiting for me to quit "fooling around with computers," go to med school, and become a radiologist? My department chairman, a manager who gives one new insight into and sympathy for disgruntled postal workers?'' and concludes with: :''Oh, yes, the acknowledgements. I think not. I did it. I did it all, by myself.''

References

External links

* *
Sourceforge project page
Unix shells Scheme (programming language) interpreters Scheme (programming language) implementations Scripting languages Software using the BSD license {{Unix-stub

Features

Example

"Acknowledgments"

See also

References

External links