echo line with var that contains few lines

Question

i have a file called 'file1.txt' that contain for exemple:

bibi.toto
jaja.bubu
vrtegbvtr.rvgtbtdtbvtd

And i want to echo some text with the var content(that contain the file1.txt lines) like that:

var=$(cat file1.txt)
echo 'hello there is $var' > final.sh

To get finaly:

final.sh content:

hello there is bibi.toto
hello there is jaja.bubu
hello there is vrtegbvtr.rvgtbtdtbvtd

The script must use busybox applets (awk, grep, sed, cat,...).

------------------------------------------

I have tried first with echo command but i get: hello there is $var even if i use double quotes (") nor {} and i can't use double quotes for echoing the content to the file because my text have some ' and " symbols.

I have also tried with sed like that:

var=$(cat file1.txt)

final.sh content:
hello there is pattern

sed "s/pattern/$var/g" final.sh

But i get: sed: unmatched '/' if i use: sed "s/pattern/\$var/g" final.sh i get: hello there is $var.

Answer 1

Try:

sed 's/^/hello there is /' file1.txt > final.sh

Or if you have to use a variable:

printf '%s\n' "$var" | sed 's/^/hello there is /' > final.sh

If you don't mind losing empty lines, you could also do:

IFS='
' # split on newline
set -o noglob # disable glob
printf 'hello there is %s\n' $var > final.sh # invoke split+glob

For your actual problem:

sed "s/.*/UPDATE ownership SET library_id = 'u-wl' where doc_id = '&';/" < file1.txt |
  sqlite "$PLAY_DB_DIR/library.db"

(note that it assumes the entries in the files don't contain ' or other special byte sequences in the sqlite language. If you can't get that guarantee, that would be a sqlite injection vulnerability at best).

Or if you need to output shell code to be executed later:

{
  echo 'sqlite "$PLAY_DB_DIR/library.db" << "EOF"'
  sed "s/.*/UPDATE ownership SET library_id = 'u-wl' where doc_id = '&';/" < file1.txt
  echo EOF
} > final.sh

Which on your sample gives:

sqlite "$PLAY_DB_DIR/library.db" << "EOF"
UPDATE ownership SET library_id = 'u-wl' where doc_id = 'bibi.toto';
UPDATE ownership SET library_id = 'u-wl' where doc_id = 'jaja.bubu';
UPDATE ownership SET library_id = 'u-wl' where doc_id = 'vrtegbvtr.rvgtbtdtbvtd';
EOF

Or if you have to run one sqlite command per query:

repl=$(cat << "EOF"
sqlite "$PLAY_DB_DIR/library.db" 'UPDATE ownership SET library_id = '\\''u-wl'\\'' where doc_id = '\\''&'\\'';'
EOF
)
sed "s@.*@$repl@" < file1.txt > final.sh

(this time in addition to a sqlite injection vulnerability, that becomes an arbitrary command execution vulnerability, if the file may contain single quote characters).

On your sample, that gives:

sqlite "$PLAY_DB_DIR/library.db" 'UPDATE ownership SET library_id = '\''u-wl'\'' where doc_id = '\''bibi.toto'\'';'
sqlite "$PLAY_DB_DIR/library.db" 'UPDATE ownership SET library_id = '\''u-wl'\'' where doc_id = '\''jaja.bubu'\'';'
sqlite "$PLAY_DB_DIR/library.db" 'UPDATE ownership SET library_id = '\''u-wl'\'' where doc_id = '\''vrtegbvtr.rvgtbtdtbvtd'\'';'

Answer 2

How about

$ readarray -t X <file
$ IFS=$'\n'
$ echo "${X[*]/#/hello there is }"
hello there is bibi.toto
hello there is jaja.bubu
hello there is vrtegbvtr.rvgtbtdtbvtd

Answer 3

ex1 :

for i in $(cat file.txt); do; echo "hello there is $i"; done

hello there is bibi.toto

hello there is jaja.bubu

hello there is vrtegbvtr.rvgtbtdtbvtd.

here is an example with loop for!

ex2:

while read linha; do echo "hello there is $linha"; done < file.txt

hello there is bibi.toto

hello there is jaja.bubu

hello there is vrtegbvtr.rvgtbtdtbvtd

so it gets each line of file file.txt

Answer 4

while read -r var; do echo hello this is $var; done < file1.txt > final.sh should do what you want. This assumes the ash shell, which I believe is the one in busybox. This uses the read builtin to read the file a line at a time into var.

An equivalent bash implementation would look like

while read -r; do echo hello this is ${REPLY}; done < file1.txt > final.sh

which utilizes bash's read builtin.

Answer 5

Thanks everyone for having help me, especially @Stéphane Chazelas and @noob. My question can to be closed, the command from Stéphane basically works but the shell in wich the script must to be works is pretty strange (problem with EOF)..

As the first command exemple from noob is a little bit simple, it works. I have used my vars like that:

for i in $(cat $file1); do echo "text blabla $i blabla" >> $file2; done

Thanks again everyone.