SPIN(1) SPIN(1)
NAME
spin - verification tool for models of concurrent systems
SYNOPSIS
spin -a [ -m ] [ -Pcpp ] file
spin [ -bglmprsv ] [ -nN ] [ -Pcpp ] file
spin -c [ -t ] [ -Pcpp ] file
spin -d [ -Pcpp ] file
spin -f ltl
spin -F file
spin -i [ -bglmprsv ] [ -nN ] [ -Pcpp ] file
spin -M [ -t ] [ -Pcpp ] file
spin -t[N] [ -bglmprsv ] [ -jN ] [ -Pcpp ] file
spin -V
DESCRIPTION
Spin is a tool for analyzing the logical consistency of
asynchronous systems, specifically distributed software and
communication protocols. A verification model of the system
is first specified in a guarded command language called
Promela. This specification language, described in the ref-
erence, allows for the modeling of dynamic creation of asyn-
chronous processes, nondeterministic case selection, loops,
gotos, local and global variables. It also allows for a
concise specification of logical correctness requirements,
including, but not restricted to, requirements expressed in
linear temporal logic.
Given a Promela model stored in file, spin can perform
interactive, guided, or random simulations of the system's
execution. It can also generate a C program that performs
an exhaustive or approximate verification of the correctness
requirements for the system.
-a Generate a verifier (model checker) for the specifica-
tion. The output is written into a set of C files,
named pan.[cbhmt], that can be compiled (pcc pan.c) to
produce an executable verifier. The online spin manu-
als (see below) contain the details on compilation and
use of the verifiers.
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-c Produce an ASCII approximation of a message sequence
chart for a random or guided (when combined with -t)
simulation run. See also option -M.
-d Produce symbol table information for the model speci-
fied in file. For each Promela object this information
includes the type, name and number of elements (if
declared as an array), the initial value (if a data
object) or size (if a message channel), the scope (glo-
bal or local), and whether the object is declared as a
variable or as a parameter. For message channels, the
data types of the message fields are listed. For
structure variables, the third field defines the name
of the structure declaration that contains the vari-
able.
-f ltl
Translate the LTL formula ltl into a never claim.
This option reads a formula in LTL syntax from the sec-
ond argument and translates it into Promela syntax (a
never claim, which is Promela's equivalent of a Büchi
Automaton). The LTL operators are written: []
(always), <> (eventually), and U (strong until). There
is no X (next) operator, to secure compatibility with
the partial order reduction rules that are applied dur-
ing the verification process. If the formula contains
spaces, it should be quoted to form a single argument
to the spin command.
-F file
Translate the LTL formula stored in file into a never
claim.
This behaves identically to option -f but will read the
formula from the file instead of from the command line.
The file should contain the formula as the first line.
Any text that follows this first line is ignored, so it
can be used to store comments or annotation on the for-
mula. (On some systems the quoting conventions of the
shell complicate the use of option -f. Option -F is
meant to solve those problems.)
-i Perform an interactive simulation, prompting the user
at every execution step that requires a nondeterminis-
tic choice to be made. The simulation proceeds without
user intervention when execution is deterministic.
-M Produce a message sequence chart in Postscript form for
a random simulation or a guided simulation (when com-
bined with -t), for the model in file, and write the
result into file.ps. See also option -c.
-m Changes the semantics of send events. Ordinarily, a
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SPIN(1) SPIN(1)
send action will be (blocked) if the target message
buffer is full. With this option a message sent to a
full buffer is lost.
-nN Set the seed for a random simulation to the integer
value N. There is no space between the -n and the inte-
ger N.
-t Perform a guided simulation, following the error trail
that was produces by an earlier verification run, see
the online manuals for the details on verification.
-V Prints the spin version number and exits.
With only a filename as an argument and no options, spin
performs a random simulation of the model specified in the
file (standard input is the default if the filename is omit-
ted). If option -i is added, the simulation is interactive,
or if option -t is added, the simulation is guided.
The simulation normally does not generate output, except
what is generated explicitly by the user within the model
with printf statements, and some details about the final
state that is reached after the simulation completes. The
group of options -bglmprsv sets the desired level of infor-
mation that the user wants about a random, guided, or inter-
active simulation run. Every line of output normally con-
tains a reference to the source line in the specification
that generated it.
-b Suppress the execution of printf statements within the
model.
-g Show at each time step the current value of global
variables.
-l In combination with option -p, show the current value
of local variables of the process.
-p Show at each simulation step which process changed
state, and what source statement was executed.
-r Show all message-receive events, giving the name and
number of the receiving process and the corresponding
the source line number. For each message parameter,
show the message type and the message channel number
and name.
-s Show all message-send events.
-v Verbose mode, add some more detail, and generate more
hints and warnings about the model.
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SPIN(1) SPIN(1)
SOURCE
/sys/src/cmd/spin
SEE ALSO
http://spinroot.com: GettingStarted.pdf, Roadmap.pdf,
Manual.pdf, WhatsNew.pdf, Exercises.pdf
G.J. Holzmann, Design and Validation of Computer Protocols,
Prentice Hall, 1991.
—, `Design and validation of protocols: a tutorial,'
Computer Networks and ISDN Systems, Vol. 25, No. 9, 1993,
pp. 981-1017.
—, `The model checker Spin,' IEEE Trans. on SE, Vol, 23, No.
5, May 1997.
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