About the Execution of 2020-gold for PolyORBLF-COL-S02J04T08
Execution Summary | |||||
Max Memory Used (MB) |
Time wait (ms) | CPU Usage (ms) | I/O Wait (ms) | Computed Result | Execution Status |
329.552 | 3600000.00 | 24060.00 | 69.70 | FFTTTFFTTTFFTTFF | normal |
Execution Chart
We display below the execution chart for this examination (boot time has been removed).
Trace from the execution
Formatting '/data/fko/mcc2021-input.r170-oct2-162089287000044.qcow2', fmt=qcow2 size=4294967296 backing_file=/data/fko/mcc2021-input.qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16
Waiting for the VM to be ready (probing ssh)
................................................................................................................................................................................................................................................................................................................................
=====================================================================
Generated by BenchKit 2-4028
Executing tool gold2020
Input is PolyORBLF-COL-S02J04T08, examination is ReachabilityFireability
Time confinement is 3600 seconds
Memory confinement is 16384 MBytes
Number of cores is 4
Run identifier is r170-oct2-162089287000044
=====================================================================
--------------------
preparation of the directory to be used:
/home/mcc/execution
total 580K
-rw-r--r-- 1 mcc users 24K May 5 16:58 CTLCardinality.txt
-rw-r--r-- 1 mcc users 159K May 10 09:43 CTLCardinality.xml
-rw-r--r-- 1 mcc users 13K May 5 16:58 CTLFireability.txt
-rw-r--r-- 1 mcc users 95K May 10 09:43 CTLFireability.xml
-rw-r--r-- 1 mcc users 4.2K May 6 14:48 GenericPropertiesDefinition.xml
-rw-r--r-- 1 mcc users 6.3K May 6 14:48 GenericPropertiesVerdict.xml
-rw-r--r-- 1 mcc users 4.0K Mar 28 16:26 LTLCardinality.txt
-rw-r--r-- 1 mcc users 25K Mar 28 16:26 LTLCardinality.xml
-rw-r--r-- 1 mcc users 2.1K Mar 28 16:27 LTLFireability.txt
-rw-r--r-- 1 mcc users 15K Mar 28 16:27 LTLFireability.xml
-rw-r--r-- 1 mcc users 3.6K Mar 27 09:20 ReachabilityCardinality.txt
-rw-r--r-- 1 mcc users 16K Mar 27 09:20 ReachabilityCardinality.xml
-rw-r--r-- 1 mcc users 2.8K Mar 25 11:53 ReachabilityFireability.txt
-rw-r--r-- 1 mcc users 14K Mar 25 11:52 ReachabilityFireability.xml
-rw-r--r-- 1 mcc users 1.9K Mar 22 09:16 UpperBounds.txt
-rw-r--r-- 1 mcc users 3.9K Mar 22 09:16 UpperBounds.xml
-rw-r--r-- 1 mcc users 5 May 5 16:51 equiv_pt
-rw-r--r-- 1 mcc users 10 May 5 16:51 instance
-rw-r--r-- 1 mcc users 5 May 5 16:51 iscolored
-rw-r--r-- 1 mcc users 154K May 5 16:51 model.pnml
--------------------
content from stdout:
=== Data for post analysis generated by BenchKit (invocation template)
The expected result is a vector of booleans
BOOL_VECTOR
here is the order used to build the result vector(from text file)
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-00
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-01
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-02
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-03
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-04
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-05
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-06
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-07
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-08
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-09
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-10
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-11
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-12
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-13
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-14
FORMULA_NAME PolyORBLF-COL-S02J04T08-ReachabilityFireability-15
=== Now, execution of the tool begins
BK_START 1621374792351
bash -c /home/mcc/BenchKit/BenchKit_head.sh 2> STDERR ; echo ; echo -n "BK_STOP " ; date -u +%s%3N
[2021-05-18 21:53:14] [INFO ] Running its-tools with arguments : [-pnfolder, /home/mcc/execution, -examination, ReachabilityFireability, -z3path, /home/mcc/BenchKit//z3/bin/z3, -yices2path, /home/mcc/BenchKit//yices/bin/yices, -timeout, 3600, -rebuildPNML]
[2021-05-18 21:53:14] [INFO ] Parsing pnml file : /home/mcc/execution/model.pnml
[2021-05-18 21:53:14] [INFO ] Detected file is not PT type :http://www.pnml.org/version-2009/grammar/symmetricnet
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.
[2021-05-18 21:53:14] [INFO ] Load time of PNML (colored model parsed with PNMLFW) : 601 ms
[2021-05-18 21:53:14] [INFO ] sort/places :
D4->DisablePollingE,DisablePollingB,Insert_Source_B,P_1119,P_2579,
Threads->AwakeTasks,IdleTasks,NotifyEventJobQueuedE,QueueJobE,P_2321,TryAllocateOneTaskE,TryAllocateOneTaskB,P_2318,EnablePollingE,EnablePollingB,FetchJobB,ScheduleTaskE_Check,ScheduleTaskB,Abort_Check_Sources_E,Abort_Check_Sources_B,NotifyEventSourceAddedB,Insert_Source_E,NotifyEventSourceAddedE,P_1113,ProcessingEvt,P_1155,nyo,P_1158,P_1159,P_1160,NotifyEventEndOfCheckSourcesB,NotifyEventEndOfCheckSourcesE,Check_Sources_B,Check_Sources_E,Idle,NotifyEventJobCompletedE,NotifyEventJobCompletedB,RunE,RunB,Perform_Work_E,Try_Check_Sources_B,Try_Check_Sources_E,P_1617,ScheduleTaskE_Idle,
D6->CreatedJobs,
Jobs->P_1725,P_1724,P_1712,AvailableJobId,
Dot->cJobCnt,JobCnt,cBlockedTasks,PollingAbort,cPollingAbort,BlockedTasks,MarkerWrite,P_1727,P_1726,MarkerRead,P_1717,P_1716,CanInjectEvent,SigAbort,NoSigAbort,P_1093,P_1095,P_1097,P_1099,cSources,cIsMonitoring,IsMonitoring,cIdleTasks,ORB_Lock,
Sources->DataOnSrc,PlaceSources,ModifiedSrc,AbourtToModifySrc,
D1->NotifyEventJobQueuedB,QueueJobB,FetchJobE,ScheduleTaskE_Work,
[2021-05-18 21:53:14] [INFO ] ms2 symmetric to ms1 in transition T_1124
[2021-05-18 21:53:14] [INFO ] ms3 symmetric to ms2 in transition T_1125
[2021-05-18 21:53:14] [INFO ] ms2 symmetric to ms1 in transition T_1125
[2021-05-18 21:53:14] [INFO ] ms3 symmetric to ms2 in transition T_1126
[2021-05-18 21:53:14] [INFO ] ms2 symmetric to ms1 in transition T_1126
[2021-05-18 21:53:14] [INFO ] ms1 symmetric to ms4 in transition T_1126
[2021-05-18 21:53:14] [INFO ] Imported 81 HL places and 65 HL transitions for a total of 614 PT places and 1300.0 transition bindings in 23 ms.
[2021-05-18 21:53:14] [INFO ] Computed order based on color domains.
[2021-05-18 21:53:14] [INFO ] Unfolded HLPN to a Petri net with 614 places and 1114 transitions in 23 ms.
[2021-05-18 21:53:14] [INFO ] Unfolded HLPN properties in 0 ms.
Parsed 16 properties from file /home/mcc/execution/ReachabilityFireability.xml in 52 ms.
Working with output stream class java.io.PrintStream
Incomplete random walk after 10000 steps, including 4 resets, run finished after 163 ms. (steps per millisecond=61 ) properties seen :[1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0]
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-14 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-13 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-12 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-10 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-08 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-07 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-02 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-01 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-00 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
Incomplete Best-First random walk after 10001 steps, including 1 resets, run finished after 113 ms. (steps per millisecond=88 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10000 steps, including 0 resets, run finished after 79 ms. (steps per millisecond=126 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10001 steps, including 1 resets, run finished after 108 ms. (steps per millisecond=92 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10001 steps, including 2 resets, run finished after 153 ms. (steps per millisecond=65 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10000 steps, including 3 resets, run finished after 83 ms. (steps per millisecond=120 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10001 steps, including 0 resets, run finished after 61 ms. (steps per millisecond=163 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10001 steps, including 2 resets, run finished after 81 ms. (steps per millisecond=123 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
[2021-05-18 21:53:15] [INFO ] Flow matrix only has 1098 transitions (discarded 16 similar events)
// Phase 1: matrix 1098 rows 614 cols
[2021-05-18 21:53:15] [INFO ] Computed 50 place invariants in 51 ms
[2021-05-18 21:53:15] [INFO ] [Real]Absence check using 14 positive place invariants in 36 ms returned sat
[2021-05-18 21:53:15] [INFO ] [Real]Absence check using 14 positive and 36 generalized place invariants in 144 ms returned unsat
[2021-05-18 21:53:16] [INFO ] [Real]Absence check using 14 positive place invariants in 14 ms returned unsat
[2021-05-18 21:53:16] [INFO ] [Real]Absence check using 14 positive place invariants in 26 ms returned sat
[2021-05-18 21:53:16] [INFO ] [Real]Absence check using 14 positive and 36 generalized place invariants in 36 ms returned unsat
[2021-05-18 21:53:16] [INFO ] [Real]Absence check using 14 positive place invariants in 22 ms returned sat
[2021-05-18 21:53:16] [INFO ] [Real]Absence check using 14 positive and 36 generalized place invariants in 40 ms returned unsat
[2021-05-18 21:53:16] [INFO ] [Real]Absence check using 14 positive place invariants in 15 ms returned unsat
[2021-05-18 21:53:16] [INFO ] [Real]Absence check using 14 positive place invariants in 19 ms returned sat
[2021-05-18 21:53:16] [INFO ] [Real]Absence check using 14 positive and 36 generalized place invariants in 39 ms returned sat
[2021-05-18 21:53:16] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2021-05-18 21:53:18] [INFO ] [Real]Absence check using state equation in 1563 ms returned sat
[2021-05-18 21:53:18] [INFO ] Solution in real domain found non-integer solution.
[2021-05-18 21:53:18] [INFO ] [Nat]Absence check using 14 positive place invariants in 24 ms returned sat
[2021-05-18 21:53:18] [INFO ] [Nat]Absence check using 14 positive and 36 generalized place invariants in 66 ms returned sat
[2021-05-18 21:53:18] [INFO ] [Nat]Adding state equation constraints to refine reachable states.
[2021-05-18 21:53:20] [INFO ] [Nat]Absence check using state equation in 2299 ms returned sat
[2021-05-18 21:53:20] [INFO ] State equation strengthened by 104 read => feed constraints.
[2021-05-18 21:53:21] [INFO ] [Nat]Added 104 Read/Feed constraints in 821 ms returned sat
[2021-05-18 21:53:21] [INFO ] Deduced a trap composed of 65 places in 132 ms
[2021-05-18 21:53:21] [INFO ] Trap strengthening (SAT) tested/added 2/1 trap constraints in 323 ms
[2021-05-18 21:53:21] [INFO ] Computed and/alt/rep : 1112/13950/1096 causal constraints in 147 ms.
[2021-05-18 21:53:23] [INFO ] Added : 85 causal constraints over 17 iterations in 1388 ms. Result :unknown
[2021-05-18 21:53:23] [INFO ] [Real]Absence check using 14 positive place invariants in 56 ms returned unsat
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-15 FALSE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-09 TRUE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-06 FALSE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-05 FALSE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-04 TRUE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-03 TRUE TECHNIQUES STRUCTURAL_REDUCTION TOPOLOGICAL SAT_SMT
Incomplete Parikh walk after 236800 steps, including 1000 resets, run finished after 657 ms. (steps per millisecond=360 ) properties seen :[0] could not realise parikh vector
Support contains 8 out of 614 places. Attempting structural reductions.
Starting structural reductions, iteration 0 : 614/614 places, 1114/1114 transitions.
Ensure Unique test removed 2 places
Performed 72 Post agglomeration using F-continuation condition.Transition count delta: 72
Iterating post reduction 0 with 74 rules applied. Total rules applied 74 place count 612 transition count 1042
Reduce places removed 72 places and 0 transitions.
Iterating post reduction 1 with 72 rules applied. Total rules applied 146 place count 540 transition count 1042
Performed 64 Pre agglomeration using Quasi-Persistent + Divergent Free condition..
Pre-agglomeration after 2 with 64 Pre rules applied. Total rules applied 146 place count 540 transition count 978
Deduced a syphon composed of 64 places in 2 ms
Reduce places removed 64 places and 0 transitions.
Iterating global reduction 2 with 128 rules applied. Total rules applied 274 place count 476 transition count 978
Performed 64 Post agglomeration using F-continuation condition.Transition count delta: 64
Deduced a syphon composed of 64 places in 1 ms
Reduce places removed 64 places and 0 transitions.
Iterating global reduction 2 with 128 rules applied. Total rules applied 402 place count 412 transition count 914
Free-agglomeration rule (complex) applied 16 times.
Iterating global reduction 2 with 16 rules applied. Total rules applied 418 place count 412 transition count 898
Reduce places removed 16 places and 0 transitions.
Iterating post reduction 2 with 16 rules applied. Total rules applied 434 place count 396 transition count 898
Applied a total of 434 rules in 129 ms. Remains 396 /614 variables (removed 218) and now considering 898/1114 (removed 216) transitions.
[2021-05-18 21:53:24] [INFO ] Flow matrix only has 882 transitions (discarded 16 similar events)
// Phase 1: matrix 882 rows 396 cols
[2021-05-18 21:53:24] [INFO ] Computed 48 place invariants in 14 ms
[2021-05-18 21:53:25] [INFO ] Dead Transitions using invariants and state equation in 1782 ms returned [788, 790, 791, 792, 793, 794, 795, 796, 797, 798, 799, 802, 804, 805, 806, 807, 808, 809, 810, 811, 812, 813, 816, 818, 819, 820, 821, 822, 823, 824, 825, 826, 827, 830, 832, 833, 834, 835, 836, 837, 838, 839, 840, 841, 844, 846, 847, 848, 849, 850, 851, 852, 853, 854, 855, 858, 860, 861, 862, 863, 864, 865, 866, 867, 868, 869, 872, 874, 875, 876, 877, 878, 879, 880, 881, 882, 883, 886, 888, 889, 890, 891, 892, 893, 894, 895, 896, 897]
Found 88 dead transitions using SMT.
Drop transitions removed 88 transitions
Dead transitions reduction (with SMT) triggered by suspicious arc values removed 88 transitions :[897, 896, 895, 894, 893, 892, 891, 890, 889, 888, 886, 883, 882, 881, 880, 879, 878, 877, 876, 875, 874, 872, 869, 868, 867, 866, 865, 864, 863, 862, 861, 860, 858, 855, 854, 853, 852, 851, 850, 849, 848, 847, 846, 844, 841, 840, 839, 838, 837, 836, 835, 834, 833, 832, 830, 827, 826, 825, 824, 823, 822, 821, 820, 819, 818, 816, 813, 812, 811, 810, 809, 808, 807, 806, 805, 804, 802, 799, 798, 797, 796, 795, 794, 793, 792, 791, 790, 788]
Starting structural reductions, iteration 1 : 396/614 places, 810/1114 transitions.
Reduce places removed 2 places and 16 transitions.
Discarding 386 places :
Also discarding 786 output transitions
Drop transitions removed 786 transitions
Graph (complete) has 2414 edges and 394 vertex of which 8 are kept as prefixes of interest. Removing 386 places using SCC suffix rule.6 ms
Iterating post reduction 0 with 3 rules applied. Total rules applied 3 place count 8 transition count 8
Reduce places removed 0 places and 8 transitions.
Deduced a syphon composed of 8 places in 0 ms
Applied a total of 3 rules in 9 ms. Remains 8 /396 variables (removed 388) and now considering 0/810 (removed 810) transitions.
Finished structural reductions, in 2 iterations. Remains : 8/614 places, 0/1114 transitions.
Deduced a syphon composed of 8 places in 0 ms
Reduce places removed 8 places and 0 transitions.
FORMULA PolyORBLF-COL-S02J04T08-ReachabilityFireability-11 FALSE TECHNIQUES TOPOLOGICAL INITIAL_STATE
All properties solved without resorting to model-checking.
--------------------
content from stderr:
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="PolyORBLF-COL-S02J04T08"
export BK_EXAMINATION="ReachabilityFireability"
export BK_TOOL="gold2020"
export BK_RESULT_DIR="/tmp/BK_RESULTS/OUTPUTS"
export BK_TIME_CONFINEMENT="3600"
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 2-4028"
echo " Executing tool gold2020"
echo " Input is PolyORBLF-COL-S02J04T08, examination is ReachabilityFireability"
echo " Time confinement is $BK_TIME_CONFINEMENT seconds"
echo " Memory confinement is 16384 MBytes"
echo " Number of cores is 4"
echo " Run identifier is r170-oct2-162089287000044"
echo "====================================================================="
echo
echo "--------------------"
echo "preparation of the directory to be used:"
tar xzf /home/mcc/BenchKit/INPUTS/PolyORBLF-COL-S02J04T08.tgz
mv PolyORBLF-COL-S02J04T08 execution
cd execution
if [ "ReachabilityFireability" = "ReachabilityDeadlock" ] || [ "ReachabilityFireability" = "UpperBounds" ] || [ "ReachabilityFireability" = "QuasiLiveness" ] || [ "ReachabilityFireability" = "StableMarking" ] || [ "ReachabilityFireability" = "Liveness" ] || [ "ReachabilityFireability" = "OneSafe" ] || [ "ReachabilityFireability" = "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 [ "ReachabilityFireability" = "UpperBounds" ] ; then
echo "The expected result is a vector of positive values"
echo NUM_VECTOR
elif [ "ReachabilityFireability" != "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 "ReachabilityFireability.txt" ] ; then
echo "here is the order used to build the result vector(from text file)"
for x in $(grep Property ReachabilityFireability.txt | cut -d ' ' -f 2 | sort -u) ; do
echo "FORMULA_NAME $x"
done
elif [ -f "ReachabilityFireability.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 '
echo "FORMULA_NAME $x"
done
elif [ "ReachabilityFireability" = "ReachabilityDeadlock" ] || [ "ReachabilityFireability" = "QuasiLiveness" ] || [ "ReachabilityFireability" = "StableMarking" ] || [ "ReachabilityFireability" = "Liveness" ] || [ "ReachabilityFireability" = "OneSafe" ] ; then
echo "FORMULA_NAME ReachabilityFireability"
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 ;