.TH SPIN 1
.SH NAME
Spin - verification of multithreaded systems
.SH SYNOPSIS
.B spin
.B -V
.br
.B spin
[
.B options
]
.I file
.SH DESCRIPTION
.I 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 language called Promela (process meta language).
This modeling language supports dynamic creation of
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.
.PP
Given a Promela model stored in
.IR file ,
.I 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 --").
.
.TP
.B -a
Generate a verifier (a model checker) for the specification.
The output is written into a set of C files named
.BR pan.[ cbhmt ] ,
that can be compiled
.RB ( "pcc pan.c" )
to produce an executable verifier.
The online
.I spin
manuals contain
the details on compilation and use of the verifiers.
.
.TP
.B -b
Do not execute printf statements in a simulation run.
.
.TP
.B -c
Produce an ASCII approximation of a message sequence
chart for a random or guided (when combined with
.BR -t )
simulation run. See also option
.BR -M .
.
.TP
.B -Dxxx
Pass
.I -Dxxx
to the preprocessor (see also
.I -E
and
.IR -I ).
.
.TP
.B -d
Produce symbol table information for the model specified in
.IR 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 (global 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 variable.
.
.TP
.B -Exxx
Pass
.I xxx
to the preprocessor (see also
.I -D
and
.IR -I ).
.
.TP
.B -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 output.
.
.TP
.BI -f " ltl"
Translate the LTL formula
.I ltl
into a
.I never
claim.
.br
This option reads a formula in LTL syntax from the second argument
and translates it into Promela syntax (a
.I never
claim, which is Promela's
equivalent of a Büchi Automaton).
The LTL operators are written:
.B []
(always),
.B <>
(eventually),
and
.B U
(strong until).  There is no
.B X
(next) operator, to secure
compatibility with the partial order reduction rules that are
applied during the verification process.
If the formula contains spaces, it should be quoted to form a
single argument to the
.I spin
command.
.br
This option has largely been replaced with the support
for inline specification of ltl formula, in Spin version 6.0.
.
.TP
.BI -F " file"
Translate the LTL formula stored in
.I file
into a
.I never
claim.
.br
This behaves identically to option
.B -f
but will read the formula from the
.I 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 formula.
(On some systems the quoting conventions of the shell complicate
the use of option
.BR -f .
Option
.B -F
is meant to solve those problems.)
.
.TP
.B -g
In combination with option
.BR -p ,
print all global variable updates in a simulation run.
.
.TP
.B -h
At the end of a simulation run, print the value of the seed
that was used for the random number generator.
By specifying the same seed with the
.B -n
option, the exact
run can be repeated later.
.
.TP
.B -I
Show the result of inlining and preprocessing.
.
.TP
.B -i
Perform an interactive simulation, prompting the user at
every execution step that requires a nondeterministic choice
to be made.  The simulation proceeds without user intervention
when execution is deterministic.
.
.TP
.BI -j N
Skip printing for the first
.I N
steps in a simulation run.
.
.TP
.B -J
Reverse the evaluation order for nested unless statements,
e.g., to match the way in which Java handles exceptions.
.
.TP
.BI -k " file"
Use the file name
.I file
as the trail-file, see also
.BR -t .
.
.TP
.B -l
In combination with option
.BR -p ,
include all local variable updates in the output of a simulation run.
.
.TP
.B -M
Produce a message sequence chart in Postscript form for a
random simulation or a guided simulation
(when combined with
.BR -t ),
for the model in
.IR file ,
and write the result into
.IR file.ps .
See also option
.BR -c .
.
.TP
.B -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.
.
.TP
.BI -n N
Set the seed for a random simulation to the integer value
.IR N .
There is no space between the
.B -n
and the integer
.IR N .
.
.TP
.BI -N " file"
Use the never claim stored in
.I file
to generate the verified (see
.BR -a ).
.
.TP
.BI -O
Use the original scope rules from pre-Spin version 6.
.
.TP
.BI -o [123]
Turn off data-flow optimization (
.IR -o1 ).
Do not hide write-only variables (
.I -o2
) during verification.
Turn off statement merging (
.I -o3
) during verification.
Turn on rendezvous optimization (
.I -o4
) during verification.
Turn on case caching (
.I -o5
) to reduce the size of pan.m,
but losing accuracy in reachability reports.
.
.TP
.BI -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.
.
.TP
.BI -P xxx
Use the command
.I xxx
for preprocessing instead of the standard C preprocessor.
.
.TP
.B -p
Include all statement executions in the output of simulation runs.
.
.TP
.BI -q N
Suppress the output generated for channel
.B N
during simulation runs.
.
.TP
.B -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.
.
.TP
.B -s
Include all send operations in the output of simulation runs.
.
.TP
.B -T
Do not automatically indent the printf output of process
.I i
with
.I i
tabs.
.
.TP
.B -t[\f2N\f1]
Perform a guided simulation, following the [\f2N\f1th] error trail that
was produces by an earlier verification 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
.BR -k .
.
.TP
.B -v
Verbose mode, add some more detail, and generate more
hints and warnings about the model.
.
.TP
.B -V
Prints the
.I spin
version number and exit.
.
.PP
With only a filename as an argument and no option flags,
.I 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
.I printf
statements, and some details about the final state that is
reached after the simulation completes.
The group of options
.B -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
.B -i
is included, the simulation i
.IR interactive ,
or if option
.B -t
or
.BI -k file
is added, the simulation is
.IR guided .
.
.SH SOURCE
.B /sys/src/cmd/spin
.SH SEE ALSO
.in +4
.ti -4
.B http://spinroot.com/spin/Man/
.br
.in -4
G.J. Holzmann,
`The Spin Model Checker (Primer and Reference Manual),'
Addison-Wesley, Reading, Mass., 2004.
.br
—, `The model checker Spin,'
.IR "IEEE Trans. on SE" ,
Vol, 23, No. 5, May 1997.
.br
—, `Design and validation of protocols: a tutorial,'
.IR "Computer Networks and ISDN Systems" ,
Vol. 25, No. 9, 1993, pp. 981-1017.
.br
—,
.IR "Design and Validation of Computer Protocols" ,
Prentice Hall, Englewood Cliffs, NJ, 1991.