fond
Model Checking Contest 2023
13th edition, Paris, France, April 26, 2023 (at TOOLympics II)
Execution of r279-smll-167863549700177
Last Updated
May 14, 2023

About the Execution of LTSMin+red for NoC3x3-PT-4B

Execution Summary
Max Memory
Used (MB)
Time wait (ms) CPU Usage (ms) I/O Wait (ms) Computed Result Execution
Status
275.979 53949.00 99423.00 703.20 T normal

Execution Chart

We display below the execution chart for this examination (boot time has been removed).

Trace from the execution

Formatting '/data/fkordon/mcc2023-input.r279-smll-167863549700177.qcow2', fmt=qcow2 size=4294967296 backing_file=/data/fkordon/mcc2023-input.qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
Waiting for the VM to be ready (probing ssh)
............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
=====================================================================
Generated by BenchKit 2-5348
Executing tool ltsminxred
Input is NoC3x3-PT-4B, examination is QuasiLiveness
Time confinement is 1800 seconds
Memory confinement is 16384 MBytes
Number of cores is 4
Run identifier is r279-smll-167863549700177
=====================================================================

--------------------
preparation of the directory to be used:
/home/mcc/execution
total 1.1M
-rw-r--r-- 1 mcc users 6.5K Feb 26 10:13 CTLCardinality.txt
-rw-r--r-- 1 mcc users 69K Feb 26 10:13 CTLCardinality.xml
-rw-r--r-- 1 mcc users 6.0K Feb 26 10:12 CTLFireability.txt
-rw-r--r-- 1 mcc users 57K Feb 26 10:12 CTLFireability.xml
-rw-r--r-- 1 mcc users 4.2K Jan 29 11:40 GenericPropertiesDefinition.xml
-rw-r--r-- 1 mcc users 3.6K Feb 25 16:28 LTLCardinality.txt
-rw-r--r-- 1 mcc users 26K Feb 25 16:28 LTLCardinality.xml
-rw-r--r-- 1 mcc users 2.1K Feb 25 16:28 LTLFireability.txt
-rw-r--r-- 1 mcc users 14K Feb 25 16:28 LTLFireability.xml
-rw-r--r-- 1 mcc users 9.2K Feb 26 10:13 ReachabilityCardinality.txt
-rw-r--r-- 1 mcc users 96K Feb 26 10:13 ReachabilityCardinality.xml
-rw-r--r-- 1 mcc users 8.2K Feb 26 10:13 ReachabilityFireability.txt
-rw-r--r-- 1 mcc users 69K Feb 26 10:13 ReachabilityFireability.xml
-rw-r--r-- 1 mcc users 1.6K Feb 25 16:28 UpperBounds.txt
-rw-r--r-- 1 mcc users 3.6K Feb 25 16:28 UpperBounds.xml
-rw-r--r-- 1 mcc users 6 Mar 5 18:23 equiv_col
-rw-r--r-- 1 mcc users 3 Mar 5 18:23 instance
-rw-r--r-- 1 mcc users 6 Mar 5 18:23 iscolored
-rw-r--r-- 1 mcc users 608K Mar 5 18:23 model.pnml

--------------------
content from stdout:

=== Data for post analysis generated by BenchKit (invocation template)

The expected result is a vector of booleans
BOOL_VECTOR

FORMULA_NAME QuasiLiveness

=== Now, execution of the tool begins

BK_START 1678893566173

bash -c /home/mcc/BenchKit/BenchKit_head.sh 2> STDERR ; echo ; echo -n "BK_STOP " ; date -u +%s%3N
Invoking MCC driver with
BK_TOOL=ltsminxred
BK_EXAMINATION=QuasiLiveness
BK_BIN_PATH=/home/mcc/BenchKit/bin/
BK_TIME_CONFINEMENT=1800
BK_INPUT=NoC3x3-PT-4B
Applying reductions before tool ltsmin
Invoking reducer
Running Version 202303021504
[2023-03-15 15:19:29] [INFO ] Running its-tools with arguments : [-pnfolder, /home/mcc/execution, -examination, QuasiLiveness, -timeout, 180, -rebuildPNML]
[2023-03-15 15:19:29] [INFO ] Parsing pnml file : /home/mcc/execution/model.pnml
[2023-03-15 15:19:30] [INFO ] Load time of PNML (sax parser for PT used): 358 ms
[2023-03-15 15:19:30] [INFO ] Transformed 2328 places.
[2023-03-15 15:19:30] [INFO ] Transformed 2701 transitions.
[2023-03-15 15:19:30] [INFO ] Found NUPN structural information;
[2023-03-15 15:19:30] [INFO ] Parsed PT model containing 2328 places and 2701 transitions and 6091 arcs in 532 ms.
Starting structural reductions in LIVENESS mode, iteration 0 : 2328/2328 places, 2701/2701 transitions.
Graph (trivial) has 2324 edges and 2328 vertex of which 1399 / 2328 are part of one of the 33 SCC in 15 ms
Free SCC test removed 1366 places
Ensure Unique test removed 1620 transitions
Reduce isomorphic transitions removed 1620 transitions.
Drop transitions removed 33 transitions
Trivial Post-agglo rules discarded 33 transitions
Performed 33 trivial Post agglomeration. Transition count delta: 33
Iterating post reduction 0 with 33 rules applied. Total rules applied 34 place count 962 transition count 1048
Reduce places removed 33 places and 0 transitions.
Iterating post reduction 1 with 33 rules applied. Total rules applied 67 place count 929 transition count 1048
Performed 494 Post agglomeration using F-continuation condition.Transition count delta: 494
Deduced a syphon composed of 494 places in 1 ms
Reduce places removed 494 places and 0 transitions.
Iterating global reduction 2 with 988 rules applied. Total rules applied 1055 place count 435 transition count 554
Applied a total of 1055 rules in 159 ms. Remains 435 /2328 variables (removed 1893) and now considering 554/2701 (removed 2147) transitions.
[2023-03-15 15:19:30] [INFO ] Flow matrix only has 488 transitions (discarded 66 similar events)
// Phase 1: matrix 488 rows 435 cols
[2023-03-15 15:19:30] [INFO ] Computed 66 place invariants in 30 ms
[2023-03-15 15:19:31] [INFO ] Implicit Places using invariants in 1204 ms returned []
[2023-03-15 15:19:31] [INFO ] Flow matrix only has 488 transitions (discarded 66 similar events)
[2023-03-15 15:19:31] [INFO ] Invariant cache hit.
[2023-03-15 15:19:32] [INFO ] State equation strengthened by 39 read => feed constraints.
[2023-03-15 15:19:33] [INFO ] Implicit Places using invariants and state equation in 1581 ms returned [13, 54, 99, 142, 209, 278, 323, 368, 415]
Discarding 9 places :
Implicit Place search using SMT with State Equation took 2831 ms to find 9 implicit places.
Starting structural reductions in LIVENESS mode, iteration 1 : 426/2328 places, 554/2701 transitions.
Graph (trivial) has 265 edges and 426 vertex of which 48 / 426 are part of one of the 24 SCC in 2 ms
Free SCC test removed 24 places
Ensure Unique test removed 48 transitions
Reduce isomorphic transitions removed 48 transitions.
Applied a total of 1 rules in 14 ms. Remains 402 /426 variables (removed 24) and now considering 506/554 (removed 48) transitions.
[2023-03-15 15:19:33] [INFO ] Flow matrix only has 440 transitions (discarded 66 similar events)
// Phase 1: matrix 440 rows 402 cols
[2023-03-15 15:19:33] [INFO ] Computed 57 place invariants in 13 ms
[2023-03-15 15:19:33] [INFO ] Implicit Places using invariants in 529 ms returned []
[2023-03-15 15:19:33] [INFO ] Flow matrix only has 440 transitions (discarded 66 similar events)
[2023-03-15 15:19:33] [INFO ] Invariant cache hit.
[2023-03-15 15:19:34] [INFO ] State equation strengthened by 15 read => feed constraints.
[2023-03-15 15:19:35] [INFO ] Implicit Places using invariants and state equation in 1141 ms returned []
Implicit Place search using SMT with State Equation took 1681 ms to find 0 implicit places.
Starting structural reductions in LIVENESS mode, iteration 2 : 402/2328 places, 506/2701 transitions.
Finished structural reductions in LIVENESS mode , in 2 iterations and 4686 ms. Remains : 402/2328 places, 506/2701 transitions.
Discarding 184 transitions out of 506. Remains 322
Initial state reduction rules removed 1 formulas.
Incomplete random walk after 10000 steps, including 135 resets, run finished after 1009 ms. (steps per millisecond=9 ) properties (out of 321) seen :279
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 6 ms. (steps per millisecond=166 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 4 ms. (steps per millisecond=250 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 8 ms. (steps per millisecond=125 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 4 ms. (steps per millisecond=250 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 5 ms. (steps per millisecond=200 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 4 ms. (steps per millisecond=250 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 4 ms. (steps per millisecond=250 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 3 ms. (steps per millisecond=333 ) properties (out of 42) seen :0
Incomplete Best-First random walk after 1001 steps, including 2 resets, run finished after 4 ms. (steps per millisecond=250 ) properties (out of 42) seen :0
Running SMT prover for 42 properties.
[2023-03-15 15:19:36] [INFO ] Flow matrix only has 440 transitions (discarded 66 similar events)
[2023-03-15 15:19:36] [INFO ] Invariant cache hit.
[2023-03-15 15:19:36] [INFO ] [Real]Absence check using 57 positive place invariants in 28 ms returned sat
[2023-03-15 15:19:38] [INFO ] After 2617ms SMT Verify possible using all constraints in real domain returned unsat :0 sat :0 real:42
[2023-03-15 15:19:39] [INFO ] [Nat]Absence check using 57 positive place invariants in 25 ms returned sat
[2023-03-15 15:19:41] [INFO ] After 1483ms SMT Verify possible using state equation in natural domain returned unsat :0 sat :42
[2023-03-15 15:19:41] [INFO ] State equation strengthened by 15 read => feed constraints.
[2023-03-15 15:19:42] [INFO ] After 1389ms SMT Verify possible using 15 Read/Feed constraints in natural domain returned unsat :0 sat :42
[2023-03-15 15:19:45] [INFO ] After 3682ms SMT Verify possible using trap constraints in natural domain returned unsat :0 sat :42
Attempting to minimize the solution found.
Minimization took 1420 ms.
[2023-03-15 15:19:46] [INFO ] After 7772ms SMT Verify possible using all constraints in natural domain returned unsat :0 sat :42
Parikh walk visited 0 properties in 50 ms.
Support contains 55 out of 402 places. Attempting structural reductions.
Starting structural reductions in REACHABILITY mode, iteration 0 : 402/402 places, 506/506 transitions.
Drop transitions removed 33 transitions
Reduce isomorphic transitions removed 33 transitions.
Iterating post reduction 0 with 33 rules applied. Total rules applied 33 place count 402 transition count 473
Discarding 26 places :
Symmetric choice reduction at 1 with 26 rule applications. Total rules 59 place count 376 transition count 440
Iterating global reduction 1 with 26 rules applied. Total rules applied 85 place count 376 transition count 440
Performed 2 Post agglomeration using F-continuation condition.Transition count delta: -28
Deduced a syphon composed of 2 places in 2 ms
Reduce places removed 2 places and 0 transitions.
Iterating global reduction 1 with 4 rules applied. Total rules applied 89 place count 374 transition count 468
Drop transitions removed 3 transitions
Reduce isomorphic transitions removed 3 transitions.
Iterating post reduction 1 with 3 rules applied. Total rules applied 92 place count 374 transition count 465
Drop transitions removed 2 transitions
Redundant transition composition rules discarded 2 transitions
Iterating global reduction 2 with 2 rules applied. Total rules applied 94 place count 374 transition count 463
Free-agglomeration rule applied 154 times.
Iterating global reduction 2 with 154 rules applied. Total rules applied 248 place count 374 transition count 309
Reduce places removed 154 places and 0 transitions.
Drop transitions removed 3 transitions
Reduce isomorphic transitions removed 3 transitions.
Graph (complete) has 627 edges and 220 vertex of which 187 are kept as prefixes of interest. Removing 33 places using SCC suffix rule.3 ms
Discarding 33 places :
Also discarding 9 output transitions
Drop transitions removed 9 transitions
Iterating post reduction 2 with 158 rules applied. Total rules applied 406 place count 187 transition count 297
Drop transitions removed 35 transitions
Reduce isomorphic transitions removed 35 transitions.
Iterating post reduction 3 with 35 rules applied. Total rules applied 441 place count 187 transition count 262
Applied a total of 441 rules in 294 ms. Remains 187 /402 variables (removed 215) and now considering 262/506 (removed 244) transitions.
Finished structural reductions in REACHABILITY mode , in 1 iterations and 294 ms. Remains : 187/402 places, 262/506 transitions.
Interrupted random walk after 874605 steps, including 2 resets, run timeout after 30001 ms. (steps per millisecond=29 ) properties seen 22
Incomplete Best-First random walk after 100000 steps, including 2 resets, run finished after 796 ms. (steps per millisecond=125 ) properties (out of 20) seen :11
Incomplete Best-First random walk after 100000 steps, including 2 resets, run finished after 683 ms. (steps per millisecond=146 ) properties (out of 9) seen :4
Incomplete Best-First random walk after 100000 steps, including 2 resets, run finished after 539 ms. (steps per millisecond=185 ) properties (out of 5) seen :1
Finished Best-First random walk after 35498 steps, including 1 resets, run visited all 4 properties in 43 ms. (steps per millisecond=825 )
Able to resolve query QuasiLiveness after proving 322 properties.
FORMULA QuasiLiveness TRUE TECHNIQUES RANDOM_WALK BESTFIRST_WALK TOPOLOGICAL INITIAL_STATE
Total runtime 49332 ms.
ITS solved all properties within timeout

BK_STOP 1678893620122

--------------------
content from stderr:

+ ulimit -s 65536
+ [[ -z '' ]]
+ export LTSMIN_MEM_SIZE=8589934592
+ LTSMIN_MEM_SIZE=8589934592
+ export PYTHONPATH=/home/mcc/BenchKit/itstools/pylibs
+ PYTHONPATH=/home/mcc/BenchKit/itstools/pylibs
+ export LD_LIBRARY_PATH=/home/mcc/BenchKit/itstools/pylibs:
+ LD_LIBRARY_PATH=/home/mcc/BenchKit/itstools/pylibs:
++ sed s/.jar//
++ perl -pe 's/.*\.//g'
++ ls /home/mcc/BenchKit/bin//../reducer/bin//../../itstools//itstools/plugins/fr.lip6.move.gal.application.pnmcc_1.0.0.202303021504.jar
+ VERSION=202303021504
+ echo 'Running Version 202303021504'
+ /home/mcc/BenchKit/bin//../reducer/bin//../../itstools//itstools/its-tools -pnfolder /home/mcc/execution -examination QuasiLiveness -timeout 180 -rebuildPNML

Sequence of Actions to be Executed by the VM

This is useful if one wants to reexecute the tool in the VM from the submitted image disk.

set -x
# this is for BenchKit: configuration of major elements for the test
export BK_INPUT="NoC3x3-PT-4B"
export BK_EXAMINATION="QuasiLiveness"
export BK_TOOL="ltsminxred"
export BK_RESULT_DIR="/tmp/BK_RESULTS/OUTPUTS"
export BK_TIME_CONFINEMENT="1800"
export BK_MEMORY_CONFINEMENT="16384"
export BK_BIN_PATH="/home/mcc/BenchKit/bin/"

# this is specific to your benchmark or test

export BIN_DIR="$HOME/BenchKit/bin"

# remove the execution directoty if it exists (to avoid increse of .vmdk images)
if [ -d execution ] ; then
rm -rf execution
fi

# this is for BenchKit: explicit launching of the test
echo "====================================================================="
echo " Generated by BenchKit 2-5348"
echo " Executing tool ltsminxred"
echo " Input is NoC3x3-PT-4B, examination is QuasiLiveness"
echo " Time confinement is $BK_TIME_CONFINEMENT seconds"
echo " Memory confinement is 16384 MBytes"
echo " Number of cores is 4"
echo " Run identifier is r279-smll-167863549700177"
echo "====================================================================="
echo
echo "--------------------"
echo "preparation of the directory to be used:"

tar xzf /home/mcc/BenchKit/INPUTS/NoC3x3-PT-4B.tgz
mv NoC3x3-PT-4B execution
cd execution
if [ "QuasiLiveness" = "ReachabilityDeadlock" ] || [ "QuasiLiveness" = "UpperBounds" ] || [ "QuasiLiveness" = "QuasiLiveness" ] || [ "QuasiLiveness" = "StableMarking" ] || [ "QuasiLiveness" = "Liveness" ] || [ "QuasiLiveness" = "OneSafe" ] || [ "QuasiLiveness" = "StateSpace" ]; then
rm -f GenericPropertiesVerdict.xml
fi
pwd
ls -lh

echo
echo "--------------------"
echo "content from stdout:"
echo
echo "=== Data for post analysis generated by BenchKit (invocation template)"
echo
if [ "QuasiLiveness" = "UpperBounds" ] ; then
echo "The expected result is a vector of positive values"
echo NUM_VECTOR
elif [ "QuasiLiveness" != "StateSpace" ] ; then
echo "The expected result is a vector of booleans"
echo BOOL_VECTOR
else
echo "no data necessary for post analysis"
fi
echo
if [ -f "QuasiLiveness.txt" ] ; then
echo "here is the order used to build the result vector(from text file)"
for x in $(grep Property QuasiLiveness.txt | cut -d ' ' -f 2 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ -f "QuasiLiveness.xml" ] ; then # for cunf (txt files deleted;-)
echo echo "here is the order used to build the result vector(from xml file)"
for x in $(grep '' QuasiLiveness.xml | cut -d '>' -f 2 | cut -d '<' -f 1 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ "QuasiLiveness" = "ReachabilityDeadlock" ] || [ "QuasiLiveness" = "QuasiLiveness" ] || [ "QuasiLiveness" = "StableMarking" ] || [ "QuasiLiveness" = "Liveness" ] || [ "QuasiLiveness" = "OneSafe" ] ; then
echo "FORMULA_NAME QuasiLiveness"
fi
echo
echo "=== Now, execution of the tool begins"
echo
echo -n "BK_START "
date -u +%s%3N
echo
timeout -s 9 $BK_TIME_CONFINEMENT bash -c "/home/mcc/BenchKit/BenchKit_head.sh 2> STDERR ; echo ; echo -n \"BK_STOP \" ; date -u +%s%3N"
if [ $? -eq 137 ] ; then
echo
echo "BK_TIME_CONFINEMENT_REACHED"
fi
echo
echo "--------------------"
echo "content from stderr:"
echo
cat STDERR ;