I have (roughly) the following code:
read -p "What is your variable: " WHATIS
cat > ./test.txt <<EOF
This should be a bunch of lines
I want this "variable" to be imbedded
it is ${WHATIS}
EOF
I keep getting the literal output of "${WHATIS}.
I did this ages ago but can not remember how or find the code I used.
Any help would be appreciated
All three of these options are working for me:
Plain echo "string" > file:
read -p "What is your variable: " WHATIS
echo "This should be a bunch of lines
I want this \"variable\" to be embedded
it is $WHATIS" > ./test.txt
cat with HEREDOC and variable expansion:
read -p "What is variable 2?: " WHATIS2
cat > ./test.txt <<EOF
This should be a bunch of lines
I want this "variable" to be embedded
it is $WHATIS2
EOF
cat withHEREDOC and variable substitution/expansion:
read -p "What is variable 3?: " WHATIS3
cat > ./test.txt <<EOF
This should be a bunch of lines
I want this "variable" to be embedded
it is ${WHATIS3}
EOF
Using ${var} instead of $var is for when you want the variable name separated from other content (like echo "${myvar}s are cool"), or when you are actually doing some extra substitution (like echo "${myvar:-mydefault}"). It doesn't hurt to use ${}, but it's not necessary.
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