I want to read a file line by line in Unix shell scripting. Line can contain leading and trailing spaces and i want to read those spaces also in the line. I tried with "while read line" but read command is removing space characters from line :( Example if line in file are:-
abcd efghijk
abcdefg hijk
line should be read as:-
1) "abcd efghijk"
2) " abcdefg hijk"
What I tried is this (which not worked):-
while read line
do
echo $line
done < file.txt
I want line including space and tab characters in it. Please suggest a way.
Try this,
IFS=''
while read line
do
echo $line
done < file.txt
EDIT:
From man bash
IFS - The Internal Field Separator that is used for word
splitting after expansion and to split lines into words
with the read builtin command. The default value is
``<space><tab><newline>''
You want to read raw lines to avoid problems with backslashes in the input (use -r):
while read -r line; do
printf "<%s>\n" "$line"
done < file.txt
This will keep whitespace within the line, but removes leading and trailing whitespace. To keep those as well, set the IFS empty, as in
while IFS= read -r line; do
printf "%s\n" "$line"
done < file.txt
This now is an equivalent of cat < file.txt as long as file.txt ends with a newline.
Note that you must double quote "$line" in order to keep word splitting from splitting the line into separate words--thus losing multiple whitespace sequences.
Source: Stackoverflow.com