fond
Model Checking Contest 2020
10th edition, Paris, France, June 23, 2020
Execution of r051-ebro-158902546300511
Last Updated
Jun 28, 2020

About the Execution of ITS-Tools for DLCround-PT-06b

Execution Summary
Max Memory
Used (MB)
Time wait (ms) CPU Usage (ms) I/O Wait (ms) Computed Result Execution
Status
15756.150 37185.00 53872.00 143.00 TTFTTTTTFFTTTTFT normal

Execution Chart

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

Trace from the execution

Formatting '/mnt/tpsp/fkordon/mcc2020-input.r051-ebro-158902546300511.qcow2', fmt=qcow2 size=4294967296 backing_file='/mnt/tpsp/fkordon/mcc2020-input.qcow2' encryption=off cluster_size=65536 lazy_refcounts=off
Waiting for the VM to be ready (probing ssh)
..........................
=====================================================================
Generated by BenchKit 2-4028
Executing tool itstools
Input is DLCround-PT-06b, examination is ReachabilityFireability
Time confinement is 3600 seconds
Memory confinement is 16384 MBytes
Number of cores is 4
Run identifier is r051-ebro-158902546300511
=====================================================================

--------------------
preparation of the directory to be used:
/home/mcc/execution
total 988K
-rw-r--r-- 1 mcc users 3.8K Mar 30 18:54 CTLCardinality.txt
-rw-r--r-- 1 mcc users 22K Mar 30 18:54 CTLCardinality.xml
-rw-r--r-- 1 mcc users 2.4K Mar 29 08:53 CTLFireability.txt
-rw-r--r-- 1 mcc users 16K Mar 29 08:53 CTLFireability.xml
-rw-r--r-- 1 mcc users 4.0K Mar 24 05:37 GenericPropertiesDefinition.xml
-rw-r--r-- 1 mcc users 5.9K Mar 24 05:37 GenericPropertiesVerdict.xml
-rw-r--r-- 1 mcc users 3.2K Apr 8 14:50 LTLCardinality.txt
-rw-r--r-- 1 mcc users 23K Apr 28 14:00 LTLCardinality.xml
-rw-r--r-- 1 mcc users 2.0K Apr 8 14:50 LTLFireability.txt
-rw-r--r-- 1 mcc users 18K Apr 28 14:00 LTLFireability.xml
-rw-r--r-- 1 mcc users 3.3K Mar 28 04:51 ReachabilityCardinality.txt
-rw-r--r-- 1 mcc users 16K Mar 28 04:51 ReachabilityCardinality.xml
-rw-r--r-- 1 mcc users 2.5K Mar 26 23:21 ReachabilityFireability.txt
-rw-r--r-- 1 mcc users 14K Mar 26 23:21 ReachabilityFireability.xml
-rw-r--r-- 1 mcc users 1.6K Mar 28 14:49 UpperBounds.txt
-rw-r--r-- 1 mcc users 3.6K Mar 28 14:49 UpperBounds.xml
-rw-r--r-- 1 mcc users 6 Mar 24 05:37 equiv_col
-rw-r--r-- 1 mcc users 4 Mar 24 05:37 instance
-rw-r--r-- 1 mcc users 6 Mar 24 05:37 iscolored
-rw-r--r-- 1 mcc users 813K Mar 24 05:37 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 DLCround-PT-06b-ReachabilityFireability-00
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-01
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-02
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-03
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-04
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-05
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-06
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-07
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-08
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-09
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-10
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-11
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-12
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-13
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-14
FORMULA_NAME DLCround-PT-06b-ReachabilityFireability-15

=== Now, execution of the tool begins

BK_START 1589609508540

[2020-05-16 06:11:51] [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, -its, -ltsminpath, /home/mcc/BenchKit//lts_install_dir/, -greatspnpath, /home/mcc/BenchKit//greatspn/, -order, META, -manyOrder, -smt, -timeout, 3600]
[2020-05-16 06:11:51] [INFO ] Parsing pnml file : /home/mcc/execution/model.pnml
[2020-05-16 06:11:52] [INFO ] Load time of PNML (sax parser for PT used): 371 ms
[2020-05-16 06:11:52] [INFO ] Transformed 2340 places.
[2020-05-16 06:11:52] [INFO ] Transformed 3456 transitions.
[2020-05-16 06:11:52] [INFO ] Found NUPN structural information;
[2020-05-16 06:11:52] [INFO ] Parsed PT model containing 2340 places and 3456 transitions in 533 ms.
Parsed 16 properties from file /home/mcc/execution/ReachabilityFireability.xml in 165 ms.
Working with output stream class java.io.PrintStream
Incomplete random walk after 10000 steps, including 0 resets, run finished after 197 ms. (steps per millisecond=50 ) properties seen :[1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0]
FORMULA DLCround-PT-06b-ReachabilityFireability-14 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-13 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-11 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-08 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-07 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-05 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-04 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-03 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-00 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
Incomplete Best-First random walk after 10001 steps, including 0 resets, run finished after 50 ms. (steps per millisecond=200 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10001 steps, including 0 resets, run finished after 46 ms. (steps per millisecond=217 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10000 steps, including 0 resets, run finished after 28 ms. (steps per millisecond=357 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10001 steps, including 0 resets, run finished after 37 ms. (steps per millisecond=270 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10001 steps, including 0 resets, run finished after 41 ms. (steps per millisecond=243 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10001 steps, including 0 resets, run finished after 30 ms. (steps per millisecond=333 ) properties seen :[0, 0, 0, 0, 0, 0, 0]
Incomplete Best-First random walk after 10001 steps, including 0 resets, run finished after 19 ms. (steps per millisecond=526 ) properties seen :[0, 0, 0, 0, 0, 0, 1]
FORMULA DLCround-PT-06b-ReachabilityFireability-15 TRUE TECHNIQUES TOPOLOGICAL BESTFIRST_WALK
// Phase 1: matrix 3456 rows 2340 cols
[2020-05-16 06:11:53] [INFO ] Computed 109 place invariants in 110 ms
[2020-05-16 06:11:54] [INFO ] [Real]Absence check using 109 positive place invariants in 389 ms returned sat
[2020-05-16 06:11:54] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-16 06:11:58] [INFO ] [Real]Absence check using state equation in 3876 ms returned (error "Solver has unexpectedly terminated")
[2020-05-16 06:11:58] [INFO ] [Real]Absence check using 109 positive place invariants in 415 ms returned sat
[2020-05-16 06:11:58] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-16 06:12:03] [INFO ] SMT solver returned unknown. Retrying;
[2020-05-16 06:12:03] [INFO ] [Real]Absence check using state equation in 4118 ms returned (error "Failed to check-sat")
[2020-05-16 06:12:03] [INFO ] [Real]Absence check using 109 positive place invariants in 371 ms returned sat
[2020-05-16 06:12:03] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-16 06:12:08] [INFO ] SMT solver returned unknown. Retrying;
[2020-05-16 06:12:08] [INFO ] [Real]Absence check using state equation in 4161 ms returned (error "Failed to check-sat")
[2020-05-16 06:12:09] [INFO ] [Real]Absence check using 109 positive place invariants in 410 ms returned sat
[2020-05-16 06:12:09] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-16 06:12:13] [INFO ] SMT solver returned unknown. Retrying;
[2020-05-16 06:12:13] [INFO ] [Real]Absence check using state equation in 3940 ms returned unknown
[2020-05-16 06:12:14] [INFO ] [Real]Absence check using 109 positive place invariants in 395 ms returned sat
[2020-05-16 06:12:14] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-16 06:12:18] [INFO ] SMT solver returned unknown. Retrying;
[2020-05-16 06:12:18] [INFO ] [Real]Absence check using state equation in 4150 ms returned (error "Failed to check-sat")
[2020-05-16 06:12:19] [INFO ] [Real]Absence check using 109 positive place invariants in 405 ms returned sat
[2020-05-16 06:12:19] [INFO ] [Real]Adding state equation constraints to refine reachable states.
[2020-05-16 06:12:23] [INFO ] SMT solver returned unknown. Retrying;
[2020-05-16 06:12:23] [INFO ] [Real]Absence check using state equation in 4134 ms returned (error "Failed to check-sat")
Support contains 35 out of 2340 places. Attempting structural reductions.
Starting structural reductions, iteration 0 : 2340/2340 places, 3456/3456 transitions.
Graph (trivial) has 2158 edges and 2340 vertex of which 456 / 2340 are part of one of the 32 SCC in 51 ms
Free SCC test removed 424 places
Drop transitions removed 474 transitions
Reduce isomorphic transitions removed 474 transitions.
Performed 852 Post agglomeration using F-continuation condition.Transition count delta: 852
Iterating post reduction 0 with 1326 rules applied. Total rules applied 1327 place count 1916 transition count 2130
Reduce places removed 852 places and 0 transitions.
Ensure Unique test removed 30 transitions
Reduce isomorphic transitions removed 30 transitions.
Performed 25 Post agglomeration using F-continuation condition.Transition count delta: 25
Iterating post reduction 1 with 907 rules applied. Total rules applied 2234 place count 1064 transition count 2075
Reduce places removed 25 places and 0 transitions.
Ensure Unique test removed 4 transitions
Reduce isomorphic transitions removed 4 transitions.
Performed 3 Post agglomeration using F-continuation condition.Transition count delta: 3
Iterating post reduction 2 with 32 rules applied. Total rules applied 2266 place count 1039 transition count 2068
Reduce places removed 3 places and 0 transitions.
Iterating post reduction 3 with 3 rules applied. Total rules applied 2269 place count 1036 transition count 2068
Performed 13 Pre agglomeration using Quasi-Persistent + Divergent Free condition..
Pre-agglomeration after 4 with 13 Pre rules applied. Total rules applied 2269 place count 1036 transition count 2055
Deduced a syphon composed of 13 places in 19 ms
Reduce places removed 13 places and 0 transitions.
Iterating global reduction 4 with 26 rules applied. Total rules applied 2295 place count 1023 transition count 2055
Symmetric choice reduction at 4 with 277 rule applications. Total rules 2572 place count 1023 transition count 2055
Deduced a syphon composed of 277 places in 15 ms
Reduce places removed 277 places and 277 transitions.
Iterating global reduction 4 with 554 rules applied. Total rules applied 3126 place count 746 transition count 1778
Ensure Unique test removed 1 transitions
Reduce isomorphic transitions removed 1 transitions.
Iterating post reduction 4 with 1 rules applied. Total rules applied 3127 place count 746 transition count 1777
Performed 112 Pre agglomeration using Quasi-Persistent + Divergent Free condition..
Pre-agglomeration after 5 with 112 Pre rules applied. Total rules applied 3127 place count 746 transition count 1665
Deduced a syphon composed of 112 places in 24 ms
Reduce places removed 112 places and 0 transitions.
Iterating global reduction 5 with 224 rules applied. Total rules applied 3351 place count 634 transition count 1665
Symmetric choice reduction at 5 with 44 rule applications. Total rules 3395 place count 634 transition count 1665
Deduced a syphon composed of 44 places in 21 ms
Reduce places removed 44 places and 425 transitions.
Iterating global reduction 5 with 88 rules applied. Total rules applied 3483 place count 590 transition count 1240
Ensure Unique test removed 16 transitions
Reduce isomorphic transitions removed 16 transitions.
Iterating post reduction 5 with 16 rules applied. Total rules applied 3499 place count 590 transition count 1224
Performed 150 Post agglomeration using F-continuation condition with reduction of 4 identical transitions.
Deduced a syphon composed of 150 places in 1 ms
Reduce places removed 150 places and 0 transitions.
Iterating global reduction 6 with 300 rules applied. Total rules applied 3799 place count 440 transition count 1070
Ensure Unique test removed 5 transitions
Reduce isomorphic transitions removed 5 transitions.
Iterating post reduction 6 with 5 rules applied. Total rules applied 3804 place count 440 transition count 1065
Performed 35 Post agglomeration using F-continuation condition with reduction of 21 identical transitions.
Deduced a syphon composed of 35 places in 1 ms
Reduce places removed 35 places and 0 transitions.
Iterating global reduction 7 with 70 rules applied. Total rules applied 3874 place count 405 transition count 1350
Drop transitions removed 11 transitions
Reduce isomorphic transitions removed 11 transitions.
Iterating post reduction 7 with 11 rules applied. Total rules applied 3885 place count 405 transition count 1339
Renaming transitions due to excessive name length > 1024 char.
Free-agglomeration rule applied 214 times with reduction of 120 identical transitions.
Iterating global reduction 8 with 214 rules applied. Total rules applied 4099 place count 405 transition count 1005
Reduce places removed 214 places and 0 transitions.
Drop transitions removed 376 transitions
Ensure Unique test removed 10 transitions
Reduce isomorphic transitions removed 386 transitions.
Iterating post reduction 8 with 600 rules applied. Total rules applied 4699 place count 191 transition count 619
Symmetric choice reduction at 9 with 5 rule applications. Total rules 4704 place count 191 transition count 619
Deduced a syphon composed of 5 places in 0 ms
Reduce places removed 5 places and 50 transitions.
Iterating global reduction 9 with 10 rules applied. Total rules applied 4714 place count 186 transition count 569
Ensure Unique test removed 3 transitions
Reduce isomorphic transitions removed 3 transitions.
Iterating post reduction 9 with 3 rules applied. Total rules applied 4717 place count 186 transition count 566
Drop transitions removed 51 transitions
Redundant transition composition rules discarded 51 transitions
Iterating global reduction 10 with 51 rules applied. Total rules applied 4768 place count 186 transition count 515
Symmetric choice reduction at 10 with 6 rule applications. Total rules 4774 place count 186 transition count 515
Deduced a syphon composed of 6 places in 1 ms
Reduce places removed 6 places and 60 transitions.
Iterating global reduction 10 with 12 rules applied. Total rules applied 4786 place count 180 transition count 455
Ensure Unique test removed 6 transitions
Reduce isomorphic transitions removed 6 transitions.
Iterating post reduction 10 with 6 rules applied. Total rules applied 4792 place count 180 transition count 449
Free-agglomeration rule applied 4 times.
Iterating global reduction 11 with 4 rules applied. Total rules applied 4796 place count 180 transition count 445
Reduce places removed 4 places and 0 transitions.
Drop transitions removed 32 transitions
Ensure Unique test removed 4 transitions
Reduce isomorphic transitions removed 36 transitions.
Iterating post reduction 11 with 40 rules applied. Total rules applied 4836 place count 176 transition count 409
Drop transitions removed 4 transitions
Redundant transition composition rules discarded 4 transitions
Iterating global reduction 12 with 4 rules applied. Total rules applied 4840 place count 176 transition count 405
Applied a total of 4840 rules in 1505 ms. Remains 176 /2340 variables (removed 2164) and now considering 405/3456 (removed 3051) transitions.
Finished structural reductions, in 1 iterations. Remains : 176/2340 places, 405/3456 transitions.
Finished random walk after 98382 steps, including 0 resets, run visited all 6 properties in 711 ms. (steps per millisecond=138 )
FORMULA DLCround-PT-06b-ReachabilityFireability-12 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-10 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-09 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-06 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-02 FALSE TECHNIQUES TOPOLOGICAL RANDOM_WALK
FORMULA DLCround-PT-06b-ReachabilityFireability-01 TRUE TECHNIQUES TOPOLOGICAL RANDOM_WALK
All properties solved without resorting to model-checking.

BK_STOP 1589609545725

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

+ export BINDIR=/home/mcc/BenchKit/
+ BINDIR=/home/mcc/BenchKit/
++ pwd
+ export MODEL=/home/mcc/execution
+ MODEL=/home/mcc/execution
+ [[ ReachabilityFireability = StateSpace ]]
+ /home/mcc/BenchKit//runeclipse.sh /home/mcc/execution ReachabilityFireability -its -ltsminpath /home/mcc/BenchKit//lts_install_dir/ -greatspnpath /home/mcc/BenchKit//greatspn/ -order META -manyOrder -smt -timeout 3600
+ ulimit -s 65536
+ [[ -z '' ]]
+ export LTSMIN_MEM_SIZE=8589934592
+ LTSMIN_MEM_SIZE=8589934592
+ /home/mcc/BenchKit//itstools/its-tools -data /home/mcc/execution/workspace -pnfolder /home/mcc/execution -examination ReachabilityFireability -z3path /home/mcc/BenchKit//z3/bin/z3 -yices2path /home/mcc/BenchKit//yices/bin/yices -its -ltsminpath /home/mcc/BenchKit//lts_install_dir/ -greatspnpath /home/mcc/BenchKit//greatspn/ -order META -manyOrder -smt -timeout 3600 -vmargs -Dosgi.locking=none -Declipse.stateSaveDelayInterval=-1 -Dosgi.configuration.area=/tmp/.eclipse -Xss128m -Xms40m -Xmx16000m -Dfile.encoding=UTF-8 -Dosgi.requiredJavaVersion=1.6

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="DLCround-PT-06b"
export BK_EXAMINATION="ReachabilityFireability"
export BK_TOOL="itstools"
export BK_RESULT_DIR="/tmp/BK_RESULTS/OUTPUTS"
export BK_TIME_CONFINEMENT="3600"
export BK_MEMORY_CONFINEMENT="16384"

# 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 itstools"
echo " Input is DLCround-PT-06b, 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 r051-ebro-158902546300511"
echo "====================================================================="
echo
echo "--------------------"
echo "preparation of the directory to be used:"

tar xzf /home/mcc/BenchKit/INPUTS/DLCround-PT-06b.tgz
mv DLCround-PT-06b 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 '' ReachabilityFireability.xml | cut -d '>' -f 2 | cut -d '<' -f 1 | sort -u) ; do
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 ;