How can I create an array from the first line of multiple text sources?
I have an array of paths to files which each have several lines of text. I'd like to produce an array that is populated with the first line of each file processed like so:
# this.txt first line is [Test this]
# another.txt first line is [Test another]
paths=(
./this/path/this.txt
./another/path/another.txt
)
for i in ${paths[@]}; do
read -r line < $i
lines+=$line
done
At most I've only gotten one value in my array. I can't seem to get the array I'm looking for out of the for loop. I've tried many variations and having a hard time figuring out where I'm going wrong.
bash shell-script array
asked 37 mins ago
dimmechdimmech
221413
add a comment |
I have an array of paths to files which each have several lines of text. I'd like to produce an array that is populated with the first line of each file processed like so:
# this.txt first line is [Test this]
# another.txt first line is [Test another]
paths=(
./this/path/this.txt
./another/path/another.txt
)
for i in ${paths[@]}; do
read -r line < $i
lines+=$line
done
At most I've only gotten one value in my array. I can't seem to get the array I'm looking for out of the for loop. I've tried many variations and having a hard time figuring out where I'm going wrong.
bash shell-script array
asked 37 mins ago
dimmechdimmech
221413
add a comment |
I have an array of paths to files which each have several lines of text. I'd like to produce an array that is populated with the first line of each file processed like so:
# this.txt first line is [Test this]
# another.txt first line is [Test another]
paths=(
./this/path/this.txt
./another/path/another.txt
)
for i in ${paths[@]}; do
read -r line < $i
lines+=$line
done
At most I've only gotten one value in my array. I can't seem to get the array I'm looking for out of the for loop. I've tried many variations and having a hard time figuring out where I'm going wrong.
bash shell-script array
asked 37 mins ago
dimmechdimmech
221413
I have an array of paths to files which each have several lines of text. I'd like to produce an array that is populated with the first line of each file processed like so:
# this.txt first line is [Test this]
# another.txt first line is [Test another]
paths=(
./this/path/this.txt
./another/path/another.txt
)
for i in ${paths[@]}; do
read -r line < $i
lines+=$line
done
At most I've only gotten one value in my array. I can't seem to get the array I'm looking for out of the for loop. I've tried many variations and having a hard time figuring out where I'm going wrong.
bash shell-script array
bash shell-script array
asked 37 mins ago
dimmechdimmech
221413
asked 37 mins ago
dimmechdimmech
221413
asked 37 mins ago
dimmechdimmech
221413
asked 37 mins ago
dimmechdimmech
221413
asked 37 mins ago
dimmechdimmech
221413
221413
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
You wanted
lines+=("$line")
+=WORD is string concatenation (or addition). A compound assignment +=(...) appends the values to the array.
You probably also want to quote all your variable expansions here - the line definitely needs it if the line might contain whitespace, but you could have issues elsewhere as well.
answered 30 mins ago
Michael HomerMichael Homer
47.8k8126165
Thanks, it makes sense now why in some of my attempts it looked like the result was a mix of the two lines.
– dimmech
18 mins ago
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
You wanted
lines+=("$line")
+=WORD is string concatenation (or addition). A compound assignment +=(...) appends the values to the array.
You probably also want to quote all your variable expansions here - the line definitely needs it if the line might contain whitespace, but you could have issues elsewhere as well.
answered 30 mins ago
Michael HomerMichael Homer
47.8k8126165
Thanks, it makes sense now why in some of my attempts it looked like the result was a mix of the two lines.
– dimmech
18 mins ago
add a comment |
You wanted
lines+=("$line")
+=WORD is string concatenation (or addition). A compound assignment +=(...) appends the values to the array.
You probably also want to quote all your variable expansions here - the line definitely needs it if the line might contain whitespace, but you could have issues elsewhere as well.
answered 30 mins ago
Michael HomerMichael Homer
47.8k8126165
Thanks, it makes sense now why in some of my attempts it looked like the result was a mix of the two lines.
– dimmech
18 mins ago
add a comment |
You wanted
lines+=("$line")
+=WORD is string concatenation (or addition). A compound assignment +=(...) appends the values to the array.
You probably also want to quote all your variable expansions here - the line definitely needs it if the line might contain whitespace, but you could have issues elsewhere as well.
answered 30 mins ago
Michael HomerMichael Homer
47.8k8126165
You wanted
lines+=("$line")
+=WORD is string concatenation (or addition). A compound assignment +=(...) appends the values to the array.
You probably also want to quote all your variable expansions here - the line definitely needs it if the line might contain whitespace, but you could have issues elsewhere as well.
answered 30 mins ago
Michael HomerMichael Homer
47.8k8126165
answered 30 mins ago
Michael HomerMichael Homer
47.8k8126165
answered 30 mins ago
Michael HomerMichael Homer
47.8k8126165
answered 30 mins ago
Michael HomerMichael Homer
47.8k8126165
47.8k8126165
Thanks, it makes sense now why in some of my attempts it looked like the result was a mix of the two lines.
– dimmech
18 mins ago
add a comment |
Thanks, it makes sense now why in some of my attempts it looked like the result was a mix of the two lines.
– dimmech
18 mins ago
Thanks, it makes sense now why in some of my attempts it looked like the result was a mix of the two lines.
– dimmech
18 mins ago
Thanks, it makes sense now why in some of my attempts it looked like the result was a mix of the two lines.
– dimmech
18 mins ago
add a comment |
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