CODEWITHSUNDEEP
stringbashshellawkwhile-loop
kumar
kumar

Reputation: 389

while read two lines as one string variable

Here is what i am trying to do: I have an out of a following command:

result=`awk /^#.*/{print;getline;print} file1.txt
echo "$result"

Output is:

#first comment
first line
#second comment
second line
#third comment
third line.

if i have to put $result into while loop and capture two lines as one string variable and print it, how can i do it?

Example:

echo "$result" | while read m
do
echo "Value of m is: $m"
done

Output is:

Value of m is:#first comment
Value of m is:first line
Value of m is:#second comment
Value of m is:second line
Value of m is:#third comment
Value of m is:third line.

But the Expected output is:

Value of m is:
#first comment
first line
Value of m is:
#second comment
second line
Value of m is:
#third comment
third line.

Upvotes: 1

Views: 5078

Answers (2)

Birei
Birei

Reputation: 36282

One way using awk. In each odd line read next one and join them between a newline character.

awk '
    FNR % 2 != 0 { 
        getline line; 
        result = $0 "\n" line; 
        print "Value:\n" result; 
    }
' infile

Assuming content of infile is:

#first comment
first line
#second comment
second line
#third comment
third line.

Running previous awk command output will be:

Value:

Value:
#first comment
first line
Value:
#second comment
second line
Value:
#third comment
third line.

Upvotes: 1

Dennis Williamson
Dennis Williamson

Reputation: 360365

while read -r first; read -r second
do
    printf '%s\n' 'Value of m is:' "$first" "$second"
done

Or if you need the lines in the variable:

while read -r first; read -r second
do
    m="$first"$'\n'"$second"
    echo 'Value of m is:'
    echo "$m"
done

Upvotes: 4

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