BSD/Unix CLI and TUI Ecology
Andrew Pantyukhin
<infofarmer@FreeBSD.org>
EuroBSDCon 2012
Warsaw, Poland

BSD/Unix
CLI and TUI
Ecology

CLI
Ecology

Ecology?
CLI?

CLI?

CLI —
terminal?
interpreter?
tools?
programming?
paradigm?

very few
studies

US Patent 6,625,590
Filed: Aug 10, 1999
Granted: Sep 23, 2003
Assignee: IBM

History

Louis Pouzin

CTSS ca. '63
RUNCOM

Multics ca. '64
shell

(later in '72:
datagram
packet comms
CYCLADES
Internets)

Bill Joy
vi ('76)
termcap

Ken Arnold
curses ('77)

Ken Arnold
curses(3) ('77)

pcurses ('82)
ncurses ('93)
...

Ecology?

Ecological
Interface
Design

interface
design
unscientific

artistic
(if lucky)

exceptions

but usually

text interface:
even less
scientific

first kept scientific
thanks to limitations

now at mercy of
each particular
developer

User-
Centered
Design

predetermined environment
explicit understanding
user involvement in design
completely defined procedures

Ecological
Interface
Design

late 80s
Kim Vicente
Jens Rasmussen
ecological
psychology

whole workflow
cognitive control
unanticipated tasks
partial understading of
constraints and complexity

applying
EID

CLI —
a resonating
display of EID

instruments vs
fixed procedures
progressive
complexity exposure
workflow-based

Flow-
based
programming

J. Paul Morrison
Data Responsive
Programming ('71)

natural
addictive
major Canadian bank
Unix shell!

Back to
CLI

terminal
interpreter
tools

Terminals

manual switching, teletypes (40s)
Teletype Model 33 ('63)
DEC VT05 ('70)
DEC VT100 ('78)
emulators (80s)

IBM
z/OS
TSO/E
ISPF

Interpreters

RUNCOM ('63)
MULTICS shell ('65)
Thomson shell ('71)
PWB shell ('75)
Bourne shell ('77)
C shell ('78)
Korn shell ('83)
Z shell ('90)

Interpreters

boot, loader
REXX
PowerShell
Perl, Ruby, Python
editing modes

Tools, Components

UNIX, BSD, GNU
do one thing well
flexible, versatile
interoperable
text-based flow

Tool flavoring

getopt
getopt_long

popt, CLAP, Tclap,
libcfg+, Argtable —
error handling
usage() generation
parameter casting

getopt study

FreeBSD base
867 getopt calls
7.4 avg opts/call
30% with params

subcommands (verbs)
RCS -> CVS, SVN, GIT

specialization
deconceptualization
even worse with ports

CLI vs TUI/GUI

learning and retention similar

perceived qualities lower for CLI

emergency
procedures

seatbelts —
cp ; mv ; rm

Lempel-Ziv
naming,
mnemonics

thank you!

discussion?