Torben: /* Parameters */

2026-01-17T05:26:58Z

Parameters

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[[Category:Linux]]
===Bash commands===
rm -rf dir # do not show warning if not existing
mkdir -p dir # do not print warning if already existing AND make needed parents

===Output===
View File
less File
Print last line of file
tail -1 File
Print last line, column 2 of file (cut expects tab separating)
tail -1 File | cut -f2
Follow changes in (log)file
tail -f File
Print file contents to std output
cat File
Filter contents of file to std output
grep "ERROR" File
Filter contents of file to std output (case-insensitive)
grep -i "error" File
Filter contents of file to std output, +2 lines before +1 following lines each
grep -B2 -A1 "ERROR" File
Print file contents to std output, starting at key word
grep -A9999999 "2016-04-19T10:38" File
Save program output (script/grep/cat...) into file
sh script.sh > log.txt # std output, (errors to terminal)
sh script.sh 1> log.txt 2> log-errors.txt # separate files
sh script.sh &> log.txt # std and errors both to 1 file
Send output to file and terminal
touch log.txt & tail -f log.txt & sh script.sh > log.txt
Piping
sh script.sh | less
Filtering of output
sh script.sh | grep tmenke

====Search file contents in dir recursively====
From [https://stackoverflow.com/posts/16957078/timeline]
grep -rn '/path/to/somewhere/' -e 'pattern'

===Input===
====Enter a value====
echo "Enter to continue, CTRL+C to cancel"
read ok

echo -n "Was? "
read var
echo "$var"

====Dialog Input====
dialog --yesno "Cleanup Old Backups First" 0 0
CleanUpBackups=$?
# yes -> 0 # no -> 1
if [ $CleanUpBackups -eq 0 ] # spaces needed!!!
then
perl /save/_save/backupPlatteAufraemen/loeschen2.pl
fi

===Loops===
Zip all subdirs
for D in `ls -d */`
do
# remove tailing /
D=${D%/}
echo === $D ====
cd $D
zip -rq9 ~/sicher/html/$D.zip .
# tar cfz ~/sicher/html/$D.tgz .
cd ..
done

Check if variable in list
if [[ "$D" =~ ^(hpmor-en/|DukeTypem2D/)$ ]]; then
echo skipping $D

Good overview of parameters for if [http://tldp.org/LDP/Bash-Beginners-Guide/html/sect_07_01.html]
<br>If
if [ -d "backup.0" ]; then
echo "gibts"
else
echo "gibts nicht"
fi
one-liner:
if [ -d "backup.0" ] ; then sudo mv backup.0 backup.1 ; fi

Check if process is running
if [ ! "$(pidof workrave)" ] ; then
nohup workrave
fi

While<br>
Normal loop
i=1
while [ $i -le 4 ] do
(( i++ ))
done
Endless loop
while true; do
# ...
echo "Enter to continue, CTRL+C to cancel"
read user_input
done
For loop
for FILE in *.txt;
do
mv "$FILE" `echo $FILE | tr ' ' '_'`
done

Check if files matching *.xml exist, store Number as string and print it
NUM=$(find $TRANSPORT/*.xml -type f 2> /dev/null |wc -l)
echo $NUM
if [ $NUM != "0" ] ; then
echo "$NUM files found, copying"
else
echo "No files found, exiting"
exit 0
fi

====Loop over contents / columns of file====
file contains tab separated columns $1 -> column1 etc.
while read line ; do
set $line
myCommit=$1
myDate=$2
echo "$myCommit ; $myDate"
done <"history-change.tsv"

===Exit upon Error===
set -e
touch /tmp/not_found.txt
echo will not reach here

===Parameters===
from [http://stackoverflow.com/questions/3534280/how-can-i-pass-a-file-argument-to-my-bash-script-using-a-terminal-command-in-lin]
OPTIONS=$(getopt -o f:t -l file:,titlepage -- "$@")
if [ $? -ne 0 ]; then
echo "getopt error"
exit 1
fi
eval set -- $OPTIONS
while true; do
case "$1" in
-f|--file) FILE="$2" ; shift ;;
-t|--titlepage) TITLEPAGE=1 ;;
--) shift ; break ;;
*) echo "unknown option: $1" ; exit 1 ;;
esac
shift
done
if [ $# -ne 0 ]; then
echo "unknown option(s): $@"
exit 1
fi

if [ ! $FILE ]; then
echo "no file given as parameter"
exit 1
fi
if [ ! -f $FILE ]; then
echo "file '$FILE' not found"
exit 1
fi
# echo "titlepage: $TITLEPAGE"
# echo "file: $FILE"
# exit 1

===Combine find and some other command e.g chmod===
# chmod for dirs
find -type d -exec chmod g+xs {} \;

# make scripts excecuteable
find . -name "*.sh" -exec chmod 744 {} \;

# remove .zip files older 30 days
find ./R*/logs/*.zip -mtime +30 -exec rm {} \;

# Copy empty Directory Structure
mkdir /Zielverzeichnis
cd Quellverzeichnis
find . -type d -depth | cpio -pvdma /Zielverzeichnis/

===sed===
If you want to replace the text 'asdf' by 'qwert' in all '*.txt' files in a directory at once, use the following command:
sed -i -e 's/asdf/qwert/g' *.txt

add a line to file
sed -i '8i\\\input{layout/hp-format}\n\\input{layout/hp-markup}\n' $target_file

delete/"grep out" lines
sed -i '/\\\input{layout\/hp-contents}/d' $target_file

insert file into file at marker
sed -i -e '/<style/r ebook/epub.css' $target_file

# -z changes the delimiter to null characters (\0) to allow for multiline matching
sed -i -z 's/<\/header>.*< p >HARRY POTTER<\/p>/<\/header>\n< p >HARRY POTTER<\/p>/' $target_file

===get filename dirname etc===
cd to parent dir
script_dir=$(dirname $0)
cd $script_dir/..

dirname file
basename file

myPath=data/de-districts/de-district_timeseries-02000.tsv
myDir=$(dirname -- "$myPath")
myFileName=$(basename -- "$myPath")
myFileExt="${myFileName##*.}"
myFileName="${myFileName%.*}"

filename without extension
FILEOLD="${FILE%.pdf}-alt.pdf"

for file in *
do
if [ -f $file ] ; then
name=${file%\.*} # name without extension
echo ${name}
fi ;
done

name=`basename /path/filename.ext .ext` # -> filename
for i in *.jpeg; do mv "$i" "`basename "$i" .jpeg`.jpg"; done

Path of current working dir
dir=$PWD

Name of current directory without path
dirname=${PWD##*/}

Location of this script
dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"

===Get Date as String===
DATE=`date +"%y-%m-%d_%H-%M"`
echo $DATE

===Count Files in Folder===
find . | wc -l
Check free inodes on partition
df -i

===Tar===
get rid of message "removing leading /": use option P

===Pause===
read -p "Press any key to start backup..."

===fstab mount discs harddrive partitions===
read UUID
sudo blkid
sudo blkid /dev/sda3

UUID=D4AE21F4AE21D032 /media/win ntfs auto,user,uid=torben,gid=torben,fmask=0177,dmask=0077,ro 0 0

UUID=f103902f-bbd6-49af-b983-b1dddedd361a /media/linux ext3 auto,user,rw 0 0

UUID=EA06-C29C /media/files vfat auto,user,utf8,uid=torben,gid=torben,fmask=0177,dmask=0077,rw 0 0

===Network Tests===
ping 10.10.10.10 -c 1
netcat / ncat / nc 10.10.10.10 8080
telnet 10.10.10.10 8080

====netcat====
Netcat is pretty cool, as it can be used to send messages between two machines, or even set files, see [https://www.digitalocean.com/community/tutorials/how-to-use-netcat-to-establish-and-test-tcp-and-udp-connections-on-a-vps]

# host1: start to listen on a port
netcat -l <PORT>
# host2: connect to host1
netcat <IP-host1> <PORT>
# now messages can be send in both ways
Transfer file
# host1: start to listen on a port
netcat -l <PORT> > received_file
# host2: send a file
netcat <IP-host1> <PORT> < original_file

====wget====
wget --no-check-certificate https://192.168.0.123:8080
wget --no-check-certificate --user=myUser --password=myPasswd https://10.10.10.10/url.xml
# DynDNS
wget -d -v "http://192.168.0.123:8080/nic/update?hostname=myhost.10.10.1.100&myip=10.10.10.12&localip=10.10.10.12" --user="u123456" --password="p123456" -O output.xml
wget --ca-certificate=MyCert.pem --user=myUser --password=myPwd https://myUrl:80/file.xml

====curl====
curl --trace /dev/stdout \
--cacert MyCert.pem \
https://myUrl:80/file.xml \
-u myUser:myPwd \
--header "Content-Type: text/xml;charset=UTF-8" \
--header "SOAPAction: http://MySoapActionURL" \
--header "Accept-Encoding: gzip, deflate" \
--data '<MySoapData>'

Access Strava API and retrieve JSON format
curl -X GET "https://www.strava.com/api/v3/athlete?access_token=1234567890" -H "accept: application/json"

==Examples==
Search for a word in some files (here *.txt)
if [ -z $1 ]; then
echo -n "Was? "
read was
else
was=$1
echo "$was"
fi
grep --color=auto -i $was *.txt

===Crontab===
# every 5 minutes
*/5 * * * * script1.sh
# every 5 minutes + 1
1-56/5 * * * * script2.sh

===systemctl Services===
# create service
sudo vim /etc/systemd/system/mqtt_influx.service

[Unit]
Description=My MQTT to InfluxDB Service

[Service]
ExecStart=/usr/bin/env python3.9 /home/pi/influx-collectors/mqtt.py
WorkingDirectory=/home/pi/influx-collectors
Restart=always
User=pi
Group=pi
Nice=10

[Install]
WantedBy=multi-user.target

# activate and start service
sudo systemctl daemon-reload
sudo systemctl enable mqtt_influx.service
sudo systemctl start mqtt_influx.service
sudo systemctl restart mqtt_influx.service
sudo systemctl stop mqtt_influx.service
sudo systemctl status mqtt_influx.service
# access log (-f = follow)
sudo journalctl -u mqtt_influx.service -f

===Clean Harddisk by filling with Zeros===
Caution: double check which device you are cleaning...
sudo dd if=/dev/zero of=/dev/sdd1 bs=1M

===Screen===
# liste anzeigen
screen -list
# neuen starten
screen -R name
# screen in Hintergrund
STRG+a d -> detact screen
Screen Start Skript in new Screen
screen -A -m -d -S myScrName ./start.sh
kill Screen Session
STRG+d
kill Background Screen Session without entering
screen -X -S myScrName quit

===PID store and kill===
Set the name of the process
bash -c "exec -a <MyName> <Command>"
kill the process by name
pkill -f MyName

get and store PID
/home/user/bin/script.sh & echo $! > script.pid
kill process using PID
kill $(cat script.pid)

===Check if running as root/sudo===
if [[ $EUID -ne 0 ]]; then
echo "E: run via sudo!!!" 2>&1
exit 1
fi

check for username
if [ `whoami` != 'torben' ]
then
echo "You must be torben to do this."
exit
fi

===Add Group and User and Set Password===
groupadd testuser
useradd testuser -g testuser
echo -e "testpass\ntestpass" | (passwd --stdin testuser)

===Monitoring open files of a process===
## check system limit
# ulimit -n
DATE=`date +"%y-%m-%d_%H-%M"`
ID=`pgrep -U username -f ProcessName`
FILES=`ls -1 /proc/$ID/fd/ | wc -l`
echo "$DATE $FILES ">> /home/user/logfile.log
## check process limit
# cat /proc/$ID/limits

===Backup Script for folder using tar and filters===
#!/bin/bash
initialdir=$PWD
DATE=`date +"%Y-%m-%d_%H-%M"`

# cd to "path of this file /.."
dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
cd $dir/..
# name of current folder = name to use for backup
name=${PWD##*/}
backupSource=$PWD

cd $backupSource/../backup/
zipDir=$(pwd)
zipTarget=$zipDir/$name-$DATE.tgz

cd $backupSource
tar cfvz $zipTarget ./ --exclude='logs/*' --exclude='import/*'

cd $initialdir

===Zip dir including hidden files===
zip -r9q myfile.zip . -x '.git/*'

===Start Stop Script for Java Application===
#!/bin/bash
# Start and Stop Linux Service for Java application
# uses java paramerter -Dname=$PROGRAM
# pgrep -f $PROGRAM
# pkill -f $PROGRAM
# with $PROGRAM = Name of directory above location of this script:
# /home/torben/Tool/bin/startscript.sh -> Tool
# STDOUT and STDERR are written into ./logs/$PROGRAM-STDOUT.log

# cd to "path of this file /.." to get dirname to use as service name
dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
cd $dir/..
dirname=${PWD##*/}
# Attention, name has to be unique on the system -> added -Service !!!
PROGRAM=$dirname-Service

# ensure that this script can only be started as user torben and not accidently as root
username=torben

jar="./MyJavaApplication.jar"
log_conf="./config/log4j2.xml"
app_params="-conf ./config/config.xml"

vm_params=" \
-Dname=$PROGRAM \
-Dlog4j.configurationFile=$log_conf \
-DLog4jContextSelector=org.apache.logging.log4j.core.async.AsyncLoggerContextSelector \
"
server_params=" \
-server -Xms512m -Xmx2048m \
-XX:+UseParallelGC \
-XX:+AggressiveOpts \
-XX:+UseFastAccessorMethods \
-XX:-OmitStackTraceInFastThrow \
-XX:+HeapDumpOnOutOfMemoryError \
-XX:HeapDumpPath=./logs/rss-heap-$(date +%Y%m%d_%H%M%S).hprof \
"
# for remote jmx access (disabled by default)
jmx_params=" \
-Djava.rmi.server.hostname=172.19.13.200 \
-Dcom.sun.management.jmxremote.port=1100 \
-Dcom.sun.management.jmxremote.local.only=false \
-Dcom.sun.management.jmxremote.authenticate=false \
-Dcom.sun.management.jmxremote.ssl=false \
"
JAVAPROGRAM="\
$vm_params \
-jar $jar $app_params \
$server_params \
"

# for remote jmx access add
# $jmx_params

# for problems with IPv6 add (i.e. if Startup takes more than 10 minute until first log entry)
#-Djava.net.preferIPv4Stack=true
#-Djava.net.preferIPv6Addresses=false

# for Java debugging:
# -Xverbose:codegen

# do not modify below here #

# Check user
if [ `whoami` != $username ]
then
echo "ERROR: Only user $username is allowed to modify this service"
exit
fi

# Functions
check() {
pgrep -U $username -f $PROGRAM >/dev/null
}
kill() {
pkill -U $username -f $PROGRAM
}
stop() {
check
if [ $? -eq 0 ]; then
kill >/dev/null
# Make sure it is stopped before returning
until [ $? -ne 0 ]; do
sleep 1
check
done
check
if [ $? -eq 0 ]; then
echo "ERROR stopping application $PROGRAM"
exit 1
else
echo "Application $PROGRAM stopped"
#rm -f /var/lock/subsys/[init script name] <--- Perhaps, this lock file has to be removed, too.
fi
else
echo "Application $PROGRAM is not running"
fi
}
start() {
check
if [ $? -eq 0 ]; then
echo "Application $PROGRAM is already running"
exit 0
fi
export LC_ALL="de_DE@euro";
export LANG=german;
nohup java $JAVAPROGRAM 0<&- &>./logs/$PROGRAM-STDOUT.log &
echo "Application $PROGRAM started"
}
restart() {
stop
start
}
status() {
check
if [ $? -eq 0 ]; then
echo "Application $PROGRAM is running"
else
echo "Application $PROGRAM is stopped"
exit 1
fi
}
#Actions
case "$1" in
start)
start
;;
stop)
stop
;;
restart)
restart
;;
status)
status
;;
*)
echo "Usage: $0 {start|stop|restart|status}"
exit 1
esac
exit 0

Linux Bash Shell Scripting - Revision history

Torben: /* Parameters */