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 44 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 44 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 44 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 44 mins ago
dimmechdimmech
221413
asked 44 mins ago
dimmechdimmech
221413
asked 44 mins ago
dimmechdimmech
221413
asked 44 mins ago
dimmechdimmech
221413
asked 44 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 38 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
25 mins ago
add a comment |
Your Answer
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "106"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
var $window = $(window),
onScroll = function(e) {
var $elem = $('.new-login-left'),
docViewTop = $window.scrollTop(),
docViewBottom = docViewTop + $window.height(),
elemTop = $elem.offset().top,
elemBottom = elemTop + $elem.height();
if ((docViewTop elemBottom)) {
StackExchange.using('gps', function() { StackExchange.gps.track('embedded_signup_form.view', { location: 'question_page' }); });
$window.unbind('scroll', onScroll);
}
};
$window.on('scroll', onScroll);
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2funix.stackexchange.com%2fquestions%2f498509%2fhow-can-i-create-an-array-from-the-first-line-of-multiple-text-sources%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
You wanted
lines+=("$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 38 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
25 mins ago
add a comment |
You wanted
lines+=("$line")
+=WORD is string concatenation (or addition). A compound assignment +=(...) appends the values to the array.
You probably also want to quote all your variable expansions here - the line definitely needs it if the line might contain whitespace, but you could have issues elsewhere as well.
answered 38 mins ago
Michael HomerMichael Homer
47.8k8126165
Thanks, it makes sense now why in some of my attempts it looked like the result was a mix of the two lines.
– dimmech
25 mins ago
add a comment |
You wanted
lines+=("$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 38 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 38 mins ago
Michael HomerMichael Homer
47.8k8126165
answered 38 mins ago
Michael HomerMichael Homer
47.8k8126165
answered 38 mins ago
Michael HomerMichael Homer
47.8k8126165
answered 38 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
25 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
25 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
25 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
25 mins ago
add a comment |
Thanks for contributing an answer to Unix & Linux Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
var $window = $(window),
onScroll = function(e) {
var $elem = $('.new-login-left'),
docViewTop = $window.scrollTop(),
docViewBottom = docViewTop + $window.height(),
elemTop = $elem.offset().top,
elemBottom = elemTop + $elem.height();
if ((docViewTop elemBottom)) {
StackExchange.using('gps', function() { StackExchange.gps.track('embedded_signup_form.view', { location: 'question_page' }); });
$window.unbind('scroll', onScroll);
}
};
$window.on('scroll', onScroll);
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2funix.stackexchange.com%2fquestions%2f498509%2fhow-can-i-create-an-array-from-the-first-line-of-multiple-text-sources%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
var $window = $(window),
onScroll = function(e) {
var $elem = $('.new-login-left'),
docViewTop = $window.scrollTop(),
docViewBottom = docViewTop + $window.height(),
elemTop = $elem.offset().top,
elemBottom = elemTop + $elem.height();
if ((docViewTop elemBottom)) {
StackExchange.using('gps', function() { StackExchange.gps.track('embedded_signup_form.view', { location: 'question_page' }); });
$window.unbind('scroll', onScroll);
}
};
$window.on('scroll', onScroll);
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
var $window = $(window),
onScroll = function(e) {
var $elem = $('.new-login-left'),
docViewTop = $window.scrollTop(),
docViewBottom = docViewTop + $window.height(),
elemTop = $elem.offset().top,
elemBottom = elemTop + $elem.height();
if ((docViewTop elemBottom)) {
StackExchange.using('gps', function() { StackExchange.gps.track('embedded_signup_form.view', { location: 'question_page' }); });
$window.unbind('scroll', onScroll);
}
};
$window.on('scroll', onScroll);
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
var $window = $(window),
onScroll = function(e) {
var $elem = $('.new-login-left'),
docViewTop = $window.scrollTop(),
docViewBottom = docViewTop + $window.height(),
elemTop = $elem.offset().top,
elemBottom = elemTop + $elem.height();
if ((docViewTop elemBottom)) {
StackExchange.using('gps', function() { StackExchange.gps.track('embedded_signup_form.view', { location: 'question_page' }); });
$window.unbind('scroll', onScroll);
}
};
$window.on('scroll', onScroll);
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
