Shell Scripting Tutorial for Beginners 20 - FOR loop to execute commands

#!/bin/bash
# for loops

echo "all the files in directory--------"
for item in *
do  
   if [ -f $item ]
   then 
     echo $item
   fi
done

echo
echo "all the directory in directory--------"
for item in *
do  
   if [ -d $item ]
   then 
     echo $item
   fi
done
echo
echo "execute list of commands--------"
for command in ls pwd date
do  
     echo "command name -> $command"
     $command
done

Shell Scripting Tutorial for Beginners 18 - FOR loop

Basic Syntax:

for VARIABLE in 1 2 3 4 5 .. N
do
 command1
 command2
 commandN
done
#OR-----------------------------------------------

for VARIABLE in file1 file2 file3
do
 command1 on $VARIABLE
 command2
 commandN
done
#OR-----------------------------------------------

for OUTPUT in $(Linux-Or-Unix-Command-Here)
do
 command1 on $OUTPUT
 command2 on $OUTPUT
 commandN
done
#OR-----------------------------------------------
for (( EXP1; EXP2; EXP3 ))
do
 command1
 command2
 command3
done

Example:

#!/bin/bash
# for loops
#Example 1 ------------------------
for i in 1 2 3 4 5
do
   echo $i
done

#Example 2 ------------------------
for i in {0..10}
do
   echo $i
done

#Example 3 ------------------------
for i in {0..10..2}
do
   echo $i
done

#Example 4 ------------------------
echo ${BASH_VERSION}
for (( i=0; i<5; i++ ))
do
   echo $i
done

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Shell Scripting Tutorial for Beginners 18 - UNTIL loop

#!/bin/bash
# until loops
n=1

# first way
echo "----until loops------first way-------------------"
until [ $n -gt 10 ]
do
    echo "$n"
    (( n++ ))
done


# second way
n=1
echo "----until loops------second way-------------------"
until (( $n > 10 ))  
do
    echo "$n"
    (( ++n ))
done

# third way
n=1
echo "----until loops------third way-------------------"
until [ $n -gt 10 ]
do
    echo "$n"
    n=$(( n+1 ))
done

output

test@test:~/Desktop$ ./hello.sh 
----until loops------first way-------------------
1
2
3
4
5
6
7
8
9
10
----until loops------second way-------------------
1
2
3
4
5
6
7
8
9
10
----until loops------third way-------------------
1
2
3
4
5
6
7
8
9
10
test@test:~/Desktop$ 

Shell Scripting Tutorial for Beginners 16 - using sleep and open termina...

#!/bin/bash
# while loops
n=1

while [ $n -le 3 ]
do
    echo "$n"
    (( n++ ))
    gnome-terminal &
done

Shell Scripting Tutorial for Beginners 15 - WHILE Loops

#!/bin/bash
# while loops
n=1

# first way
echo "----while loops------first way-------------------"
while [ $n -le 10 ]
do
    echo "$n"
    (( n++ ))
done


# second way
n=1
echo "----while loops------second way-------------------"
while (( $n <= 10 ))  
do
    echo "$n"
    (( ++n ))
done

# third way
n=1
echo "----while loops------third way-------------------"
while [ $n -le 10 ]
do
    echo "$n"
    n=$(( n+1 ))
done

output:

test@test:~/Desktop$ ./hello.sh 
----while loops------first way-------------------
1
2
3
4
5
6
7
8
9
10
----while loops------second way-------------------
1
2
3
4
5
6
7
8
9
10
----while loops------third way-------------------
1
2
3
4
5
6
7
8
9
10
test@test:~/Desktop$