SPIN(1) SPIN(1)
NAME
spin - verification tool for models of concurrent systems
SYNOPSIS
spin [ options ] file
spin -V
DESCRIPTION
Spin is a tool for analyzing the logical consistency of
asynchronous systems, specifically distributed software,
multi-threaded systems, and communication protocols. A
model of the system is specified in a guarded command lan-
guage called Promela (process meta language). This modeling
language supports dynamic creation of processes, nondeter-
ministic 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 verification of the correctness requirements
for the system. The main options supported are as follows.
(You can always get a full list of current options with the
command "spin --").
-a Generate a verifier (a model checker) for the speci-
fication. 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 manuals contain the details on compilation and
use of the verifiers.
-b Do not execute printf statements in a simulation run.
-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.
-Dxxx Pass -Dxxx to the preprocessor (see also -E and -I).
-d Produce symbol table information for the model speci-
fied in file. For each Promela object this informa-
tion 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 (global or local), and whether the object is
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declared as a variable or as a parameter. For mes-
sage 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 variable.
-Exxx Pass xxx to the preprocessor (see also -D and -I).
-e If the specification contains multiple never claims,
or ltl properties, compute the synchronous product of
all claims and write the result to the standard out-
put.
-f ltl Translate the LTL formula ltl into a never claim.
This option reads a formula in LTL syntax from the
second 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 compatibil-
ity with the partial order reduction rules that are
applied during the verification process. If the for-
mula contains spaces, it should be quoted to form a
single argument to the spin command.
This option has largely been replaced with the sup-
port for inline specification of ltl formula, in Spin
version 6.0.
-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 anno-
tation on the formula. (On some systems the quoting
conventions of the shell complicate the use of option
-f. Option -F is meant to solve those problems.)
-g In combination with option -p, print all global vari-
able updates in a simulation run.
-h At the end of a simulation run, print the value of
the seed that was used for the random number genera-
tor. By specifying the same seed with the -n option,
the exact run can be repeated later.
-I Show the result of inlining and preprocessing.
-i Perform an interactive simulation, prompting the user
at every execution step that requires a
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nondeterministic choice to be made. The simulation
proceeds without user intervention when execution is
deterministic.
-jN Skip printing for the first N steps in a simulation
run.
-J Reverse the evaluation order for nested unless state-
ments, e.g., to match the way in which Java handles
exceptions.
-k file
Use the file name file as the trail-file, see also
-t.
-l In combination with option -p, include all local
variable updates in the output of a simulation run.
-M Produce a message sequence chart in Postscript form
for a random simulation or a guided simulation (when
combined 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
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
integer N.
-N file
Use the never claim stored in file to generate the
verified (see -a).
-O Use the original scope rules from pre-Spin version 6.
-o[123]
Turn off data-flow optimization ( -o1). Do not hide
write-only variables ( -o2 ) during verification.
Turn off statement merging ( -o3 ) during verifica-
tion. Turn on rendezvous optimization ( -o4 ) during
verification. Turn on case caching ( -o5 ) to reduce
the size of pan.m, but losing accuracy in reachabil-
ity reports.
-O Use the scope rules pre-version 6.0. In this case
there are only two possible levels of scope for all
data declarations: global, or proctype local. In
version 6.0 and later there is a third level of
scope: inlines or blocks.
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-Pxxx Use the command xxx for preprocessing instead of the
standard C preprocessor.
-p Include all statement executions in the output of
simulation runs.
-qN Suppress the output generated for channel N during
simulation runs.
-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 Include all send operations in the output of simula-
tion runs.
-T Do not automatically indent the printf output of pro-
cess i with i tabs.
-t[N] Perform a guided simulation, following the [Nth]
error trail that was produces by an earlier verifica-
tion run, see the online manuals for the details on
verification. By default the error trail is looked
for in a file with the same basename as the model,
and with extension .trail. See also -k.
-v Verbose mode, add some more detail, and generate more
hints and warnings about the model.
-V Prints the spin version number and exit.
With only a filename as an argument and no option flags,
spin performs a random simulation of the model specified in
the file. This 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 -bgilmprstv is used to set the desired
level of information that the user wants about a random,
guided, or interactive simulation run. Every line of output
normally contains a reference to the source line in the
specification that generated it. If option -i is included,
the simulation i interactive, or if option -t or -kfile is
added, the simulation is guided.
SOURCE
/sys/src/cmd/spin
SEE ALSO
http://spinroot.com/spin/Man/
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G.J. Holzmann, The Spin Model Checker (Primer and Reference
Manual), .}f Addison-Wesley, Reading, Mass., 2004.
—, `The model checker Spin,' IEEE Trans. on SE, Vol, 23, No.
5, May 1997.
—, `Design and validation of protocols: a tutorial,'
Computer Networks and ISDN Systems, Vol. 25, No. 9, 1993,
pp. 981-1017.
—, Design and Validation of Computer Protocols, Prentice
Hall, Englewood Cliffs, NJ, 1991.
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