Howto bash
==========

# shebang
#!/bin/bash

# print text to console:
echo 'text'

# read variable from console:
read anweisung

# if statement:
if [ "$anweisung" = "2" ]; then
..
elseif
..
fi

if [ "$volume" -lt "2" ]; then
..
fi
if [ "$volume" -gt "2" ]; then
..
fi

# while-loop:
while true;do
..
done

# For loop
#!/bin/bash
       for i in $( ls ); do
           echo item: $i
       done

# For loop with variable (works only in ksh)
#!/bin/ksh
t=5
n=1
       for i in (1..$t); do
       let 'n=n+1'
       done

# For loop with variable
#!/bin/bash
t=5
n=1
       for i in $(seq 1 $t); do
       let 'n=n+1'
       done

# initialize bash-script:
#!/bin/bash

# read file records.txt and print row wise:
while read p; do
echo $p
done <records.txt

# write text to file:
echo $p > copy.txt

# append test to file:
echo $p >> copy.txt

# clear history
history -c; hitory -w

# concatenate two strings
VAR1='Hello'
VAR2='World'
C=$VAR1" "$VAR2
echo $C

# wait for a process to finish
wait <PID>

# delay execution
sleep 5
sleep 1m 10s

# loop over files
https://www.cyberciti.biz/faq/bash-loop-over-file/

# escape character and line break
\

# compile
shc -f script.sh -o binary_name