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Android Studio React Native Build fails

I took the project I am developing at my workplace home and wanted to run it here on my machine.
I got many many errors which I fixed, but there are some that I don't know how. Maybe you guys know a fix.
\android\app\build\intermediates\external_file_lib_dex_archives\debug\out
this output get generated when building the project from AS.
I read that the fix is to add this: android.enableBuildCache=false to gradle.properties but when I do that I get this error which make 0 sense tbh.
: Cannot parse project property android.enableBuildCache='false ' of type 'class java.lang.String' as boolean. Expected 'true' or 'false'.
EDIT: Ok there was an empty space after false hence the second error but even with that corrected I get the first error.
Running it from vsCode gives me: Execution failed for task ':app:processDebugResources'.
EDIT2: Newest Error in AS:
> Task :app:mergeExtDexDebug
java.nio.file.NoSuchFileException: C:\Users\Faded\Desktop\Development\React Native\FitnessApp\FitnessApp\android\app\build\intermediates\external_file_lib_dex_archives\debug\out
at sun.nio.fs.WindowsException.translateToIOException(WindowsException.java:79)
at sun.nio.fs.WindowsException.rethrowAsIOException(WindowsException.java:97)
at sun.nio.fs.WindowsException.rethrowAsIOException(WindowsException.java:102)
at sun.nio.fs.WindowsDirectoryStream.<init>(WindowsDirectoryStream.java:80)
at sun.nio.fs.WindowsFileSystemProvider.newDirectoryStream(WindowsFileSystemProvider.java:522)
at java.nio.file.Files.newDirectoryStream(Files.java:457)
at java.nio.file.Files.list(Files.java:3451)
at com.android.build.gradle.internal.tasks.DexMergingParams.getAllDexFiles(DexMergingTask.kt:502)
at com.android.build.gradle.internal.tasks.DexMergingTaskRunnable.run(DexMergingTask.kt:423)
at com.android.build.gradle.internal.tasks.Workers$ActionFacade.run(Workers.kt:335)
at org.gradle.workers.internal.AdapterWorkAction.execute(AdapterWorkAction.java:50)
at org.gradle.workers.internal.DefaultWorkerServer.execute(DefaultWorkerServer.java:50)
at org.gradle.workers.internal.NoIsolationWorkerFactory$1$1$1.create(NoIsolationWorkerFactory.java:65)
at org.gradle.workers.internal.NoIsolationWorkerFactory$1$1$1.create(NoIsolationWorkerFactory.java:61)
at org.gradle.internal.classloader.ClassLoaderUtils.executeInClassloader(ClassLoaderUtils.java:98)
at org.gradle.workers.internal.NoIsolationWorkerFactory$1$1.execute(NoIsolationWorkerFactory.java:61)
at org.gradle.workers.internal.AbstractWorker$1.call(AbstractWorker.java:44)
at org.gradle.workers.internal.AbstractWorker$1.call(AbstractWorker.java:41)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:416)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$CallableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:406)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$1.execute(DefaultBuildOperationExecutor.java:165)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:250)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:158)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.call(DefaultBuildOperationExecutor.java:102)
at org.gradle.internal.operations.DelegatingBuildOperationExecutor.call(DelegatingBuildOperationExecutor.java:36)
at org.gradle.workers.internal.AbstractWorker.executeWrappedInBuildOperation(AbstractWorker.java:41)
at org.gradle.workers.internal.NoIsolationWorkerFactory$1.execute(NoIsolationWorkerFactory.java:53)
at org.gradle.workers.internal.DefaultWorkerExecutor$3.call(DefaultWorkerExecutor.java:217)
at org.gradle.workers.internal.DefaultWorkerExecutor$3.call(DefaultWorkerExecutor.java:212)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at org.gradle.internal.work.DefaultConditionalExecutionQueue$ExecutionRunner.runExecution(DefaultConditionalExecutionQueue.java:215)
at org.gradle.internal.work.DefaultConditionalExecutionQueue$ExecutionRunner.runBatch(DefaultConditionalExecutionQueue.java:164)
at org.gradle.internal.work.DefaultConditionalExecutionQueue$ExecutionRunner.run(DefaultConditionalExecutionQueue.java:131)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:48)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:56)
at java.lang.Thread.run(Thread.java:748)
> Task :app:transformClassesWithDexBuilderForDebug
> Task :app:validateSigningDebug UP-TO-DATE
> Task :app:signingConfigWriterDebug
> Task :app:mergeDebugJavaResource
> Task :app:mergeExtDexDebug FAILED
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:mergeExtDexDebug'.
> A failure occurred while executing com.android.build.gradle.internal.tasks.Workers$ActionFacade
> java.nio.file.NoSuchFileException: C:\Users\Faded\Desktop\Development\React Native\FitnessApp\FitnessApp\android\app\build\intermediates\external_file_lib_dex_archives\debug\out
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/6.0.1/userguide/command_line_interface.html#sec:command_line_warnings
BUILD FAILED in 19s
150 actionable tasks: 147 executed, 3 up-to-date

Try to delete the .gradle folder from projectname/android - folder and rebuild. Solved it for me.

I have encountered a similar error before. As a result of my research as a solution
In the android/app/build.gradle file multiDexEnabled true
android {
defaultConfig {
...
targetSdkVersion 28
multiDexEnabled true // here
}
...
}

As Murat Kızılöz suggested, you can get around this by adding multiDexEnabled truein the android/app/build.gradle file.
This is because Android system has a 64K reference limit
In Android, the compilers convert your source code into DEX files. This DEX file
contains the compiled code used to run the app. But there is a limitation with the
DEX file. The DEX file limits the total number of methods that can be referenced
within a single DEX file to 64K i.e. 65,536 methods. So, you cant use more than
64K methods in a particular DEX file. These 64K methods include Android framework
methods, library methods, and methods in our code also. This limit of 64K is
referred to as the "64K reference limit".
So, if our app exceeds 65,536 methods, we will encounter a build error that indicates our app has reached the limit of the Android build architecture.
To get around this, you can manually enable this in the app build.gradle file
You can read more about this at Android Multidex

Try this command in your project root:
cd android && rm -rf .gradle && rm -rf .idea
and then
./gradlew clean
and then build again, works like a charm.

You can solve this issue by deleting the .gradle folder from "NameOfProject/android" and again running Android-Studio, I hoped this is solved. :))

Node.js heap out of memory

Today I ran my script for filesystem indexing to refresh RAID files index and after 4h it crashed with following error:
[md5:] 241613/241627 97.5%
[md5:] 241614/241627 97.5%
[md5:] 241625/241627 98.1%
Creating missing list... (79570 files missing)
Creating new files list... (241627 new files)
<--- Last few GCs --->
11629672 ms: Mark-sweep 1174.6 (1426.5) -> 1172.4 (1418.3) MB, 659.9 / 0 ms [allocation failure] [GC in old space requested].
11630371 ms: Mark-sweep 1172.4 (1418.3) -> 1172.4 (1411.3) MB, 698.9 / 0 ms [allocation failure] [GC in old space requested].
11631105 ms: Mark-sweep 1172.4 (1411.3) -> 1172.4 (1389.3) MB, 733.5 / 0 ms [last resort gc].
11631778 ms: Mark-sweep 1172.4 (1389.3) -> 1172.4 (1368.3) MB, 673.6 / 0 ms [last resort gc].
<--- JS stacktrace --->
==== JS stack trace =========================================
Security context: 0x3d1d329c9e59 <JS Object>
1: SparseJoinWithSeparatorJS(aka SparseJoinWithSeparatorJS) [native array.js:~84] [pc=0x3629ef689ad0] (this=0x3d1d32904189 <undefined>,w=0x2b690ce91071 <JS Array[241627]>,L=241627,M=0x3d1d329b4a11 <JS Function ConvertToString (SharedFunctionInfo 0x3d1d3294ef79)>,N=0x7c953bf4d49 <String[4]\: ,\n >)
2: Join(aka Join) [native array.js:143] [pc=0x3629ef616696] (this=0x3d1d32904189 <undefin...
FATAL ERROR: CALL_AND_RETRY_LAST Allocation failed - JavaScript heap out of memory
1: node::Abort() [/usr/bin/node]
2: 0xe2c5fc [/usr/bin/node]
3: v8::Utils::ReportApiFailure(char const*, char const*) [/usr/bin/node]
4: v8::internal::V8::FatalProcessOutOfMemory(char const*, bool) [/usr/bin/node]
5: v8::internal::Factory::NewRawTwoByteString(int, v8::internal::PretenureFlag) [/usr/bin/node]
6: v8::internal::Runtime_SparseJoinWithSeparator(int, v8::internal::Object**, v8::internal::Isolate*) [/usr/bin/node]
7: 0x3629ef50961b
Server is equipped with 16gb RAM and 24gb SSD swap. I highly doubt my script exceeded 36gb of memory. At least it shouldn't
Script creates index of files stored as Array of Objects with files metadata (modification dates, permissions, etc, no big data)
Here's full script code:
http://pastebin.com/mjaD76c3
I've already experiend weird node issues in the past with this script what forced me eg. split index into multiple files as node was glitching when working on such big files as String. Is there any way to improve nodejs memory management with huge datasets?

If I remember correctly, there is a strict standard limit for the memory usage in V8 of around 1.7 GB, if you do not increase it manually.
In one of our products we followed this solution in our deploy script:
node --max-old-space-size=4096 yourFile.js
There would also be a new space command but as I read here: a-tour-of-v8-garbage-collection the new space only collects the newly created short-term data and the old space contains all referenced data structures which should be in your case the best option.

If you want to increase the memory usage of the node globally - not only single script, you can export environment variable, like this:
export NODE_OPTIONS=--max_old_space_size=4096
Then you do not need to play with files when running builds like
npm run build.

Just in case anyone runs into this in an environment where they cannot set node properties directly (in my case a build tool):
NODE_OPTIONS="--max-old-space-size=4096" node ...
You can set the node options using an environment variable if you cannot pass them on the command line.

Here are some flag values to add some additional info on how to allow more memory when you start up your node server.
1GB - 8GB
#increase to 1gb
node --max-old-space-size=1024 index.js
#increase to 2gb
node --max-old-space-size=2048 index.js
#increase to 3gb
node --max-old-space-size=3072 index.js
#increase to 4gb
node --max-old-space-size=4096 index.js
#increase to 5gb
node --max-old-space-size=5120 index.js
#increase to 6gb
node --max-old-space-size=6144 index.js
#increase to 7gb
node --max-old-space-size=7168 index.js
#increase to 8gb
node --max-old-space-size=8192 index.js

I just faced same problem with my EC2 instance t2.micro which has 1 GB memory.
I resolved the problem by creating swap file using this url and set following environment variable.
export NODE_OPTIONS=--max_old_space_size=4096
Finally the problem has gone.
I hope that would be helpful for future.

i was struggling with this even after setting --max-old-space-size.
Then i realised need to put options --max-old-space-size before the karma script.
also best to specify both syntaxes --max-old-space-size and --max_old_space_size my script for karma :
node --max-old-space-size=8192 --optimize-for-size --max-executable-size=8192 --max_old_space_size=8192 --optimize_for_size --max_executable_size=8192 node_modules/karma/bin/karma start --single-run --max_new_space_size=8192 --prod --aot
reference https://github.com/angular/angular-cli/issues/1652

I encountered this issue when trying to debug with VSCode, so just wanted to add this is how you can add the argument to your debug setup.
You can add it to the runtimeArgs property of your config in launch.json.
See example below.
{
"version": "0.2.0",
"configurations": [{
"type": "node",
"request": "launch",
"name": "Launch Program",
"program": "${workspaceRoot}\\server.js"
},
{
"type": "node",
"request": "launch",
"name": "Launch Training Script",
"program": "${workspaceRoot}\\training-script.js",
"runtimeArgs": [
"--max-old-space-size=4096"
]
}
]}

I had a similar issue while doing AOT angular build. Following commands helped me.
npm install -g increase-memory-limit
increase-memory-limit
Source: https://geeklearning.io/angular-aot-webpack-memory-trick/

I just want to add that in some systems, even increasing the node memory limit with --max-old-space-size, it's not enough and there is an OS error like this:
terminate called after throwing an instance of 'std::bad_alloc'
what(): std::bad_alloc
Aborted (core dumped)
In this case, probably is because you reached the max mmap per process.
You can check the max_map_count by running
sysctl vm.max_map_count
and increas it by running
sysctl -w vm.max_map_count=655300
and fix it to not be reset after a reboot by adding this line
vm.max_map_count=655300
in /etc/sysctl.conf file.
Check here for more info.
A good method to analyse the error is by run the process with strace
strace node --max-old-space-size=128000 my_memory_consuming_process.js

I've faced this same problem recently and came across to this thread but my problem was with React App. Below changes in the node start command solved my issues.
Syntax
node --max-old-space-size=<size> path-to/fileName.js
Example
node --max-old-space-size=16000 scripts/build.js
Why size is 16000 in max-old-space-size?
Basically, it varies depends on the allocated memory to that thread and your node settings.
How to verify and give right size?
This is basically stay in our engine v8. below code helps you to understand the Heap Size of your local node v8 engine.
const v8 = require('v8');
const totalHeapSize = v8.getHeapStatistics().total_available_size;
const totalHeapSizeGb = (totalHeapSize / 1024 / 1024 / 1024).toFixed(2);
console.log('totalHeapSizeGb: ', totalHeapSizeGb);

Steps to fix this issue (In Windows) -
Open command prompt and type %appdata% press enter
Navigate to %appdata% > npm folder
Open or Edit ng.cmd in your favorite editor
Add --max_old_space_size=8192 to the IF and ELSE block
Your node.cmd file looks like this after the change:
#IF EXIST "%~dp0\node.exe" (
"%~dp0\node.exe" "--max_old_space_size=8192" "%~dp0\node_modules\#angular\cli\bin\ng" %*
) ELSE (
#SETLOCAL
#SET PATHEXT=%PATHEXT:;.JS;=;%
node "--max_old_space_size=8192" "%~dp0\node_modules\#angular\cli\bin\ng" %*
)

Recently, in one of my project ran into same problem. Tried couple of things which anyone can try as a debugging to identify the root cause:
As everyone suggested , increase the memory limit in node by adding this command:
{
"scripts":{
"server":"node --max-old-space-size={size-value} server/index.js"
}
}
Here size-value i have defined for my application was 1536 (as my kubernetes pod memory was 2 GB limit , request 1.5 GB)
So always define the size-value based on your frontend infrastructure/architecture limit (little lesser than limit)
One strict callout here in the above command, use --max-old-space-size after node command not after the filename server/index.js.
If you have ngnix config file then check following things:
worker_connections: 16384 (for heavy frontend applications)
[nginx default is 512 connections per worker, which is too low for modern applications]
use: epoll (efficient method) [nginx supports a variety of connection processing methods]
http: add following things to free your worker from getting busy in handling some unwanted task. (client_body_timeout , reset_timeout_connection , client_header_timeout,keepalive_timeout ,send_timeout).
Remove all logging/tracking tools like APM , Kafka , UTM tracking, Prerender (SEO) etc middlewares or turn off.
Now code level debugging: In your main server file , remove unwanted console.log which is just printing a message.
Now check for every server route i.e app.get() , app.post() ... below scenarios:
data => if(data) res.send(data) // do you really need to wait for data or that api returns something in response which i have to wait for?? , If not then modify like this:
data => res.send(data) // this will not block your thread, apply everywhere where it's needed
else part: if there is no error coming then simply return res.send({}) , NO console.log here.
error part: some people define as error or err which creates confusion and mistakes. like this:
`error => { next(err) } // here err is undefined`
`err => {next(error) } // here error is undefined`
`app.get(API , (re,res) =>{
error => next(error) // here next is not defined
})`
remove winston , elastic-epm-node other unused libraries using npx depcheck command.
In the axios service file , check the methods and logging properly or not like :
if(successCB) console.log("success") successCB(response.data) // here it's wrong statement, because on success you are just logging and then `successCB` sending outside the if block which return in failure case also.
Save yourself from using stringify , parse etc on accessive large dataset. (which i can see in your above shown logs too.
Last but not least , for every time when your application crashes or pods restarted check the logs. In log specifically look for this section: Security context
This will give you why , where and who is the culprit behind the crash.

I will mention 2 types of solution.
My solution : In my case I add this to my environment variables :
export NODE_OPTIONS=--max_old_space_size=20480
But even if I restart my computer it still does not work. My project folder is in d:\ disk. So I remove my project to c:\ disk and it worked.
My team mate's solution : package.json configuration is worked also.
"start": "rimraf ./build && react-scripts --expose-gc --max_old_space_size=4096 start",

For other beginners like me, who didn't find any suitable solution for this error, check the node version installed (x32, x64, x86). I have a 64-bit CPU and I've installed x86 node version, which caused the CALL_AND_RETRY_LAST Allocation failed - JavaScript heap out of memory error.

if you want to change the memory globally for node (windows) go to advanced system settings -> environment variables -> new user variable
variable name = NODE_OPTIONS
variable value = --max-old-space-size=4096

You can also change Window's environment variables with:
$env:NODE_OPTIONS="--max-old-space-size=8192"

Unix (Mac OS)
Open a terminal and open our .zshrc file using nano like so (this will create one, if one doesn't exist):
nano ~/.zshrc
Update our NODE_OPTIONS environment variable by adding the following line into our currently open .zshrc file:
export NODE_OPTIONS=--max-old-space-size=8192 # increase node memory limit
Please note that we can set the number of megabytes passed in to whatever we like, provided our system has enough memory (here we are passing in 8192 megabytes which is roughly 8 GB).
Save and exit nano by pressing: ctrl + x, then y to agree and finally enter to save the changes.
Close and reopen the terminal to make sure our changes have been recognised.
We can print out the contents of our .zshrc file to see if our changes were saved like so: cat ~/.zshrc.
Linux (Ubuntu)
Open a terminal and open the .bashrc file using nano like so:
nano ~/.bashrc
The remaining steps are similar with the Mac steps from above, except we would most likely be using ~/.bashrc by default (as opposed to ~/.zshrc). So these values would need to be substituted!
Link to Nodejs Docs

Use the option --optimize-for-size. It's going to focus on using less ram.

I had this error on AWS Elastic Beanstalk, upgrading instance type from t3.micro (Free tier) to t3.small fixed the error

In my case, I upgraded node.js version to latest (version 12.8.0) and it worked like a charm.

Upgrade node to the latest version. I was on node 6.6 with this error and upgraded to 8.9.4 and the problem went away.

For Angular, this is how I fixed
In Package.json, inside script tag add this
"scripts": {
"build-prod": "node --max_old_space_size=5048 ./node_modules/#angular/cli/bin/ng build --prod",
},
Now in terminal/cmd instead of using ng build --prod just use
npm run build-prod
If you want to use this configuration for build only just remove --prod from all the 3 places

I experienced the same problem today. The problem for me was, I was trying to import lot of data to the database in my NextJS project.
So what I did is, I installed win-node-env package like this:
yarn add win-node-env
Because my development machine was Windows. I installed it locally than globally. You can install it globally also like this: yarn global add win-node-env
And then in the package.json file of my NextJS project, I added another startup script like this:
"dev_more_mem": "NODE_OPTIONS=\"--max_old_space_size=8192\" next dev"
Here, am passing the node option, ie. setting 8GB as the limit.
So my package.json file somewhat looks like this:
{
"name": "my_project_name_here",
"version": "1.0.0",
"private": true,
"scripts": {
"dev": "next dev",
"dev_more_mem": "NODE_OPTIONS=\"--max_old_space_size=8192\" next dev",
"build": "next build",
"lint": "next lint"
},
......
}
And then I run it like this:
yarn dev_more_mem
For me, I was facing the issue only on my development machine (because I was doing the importing of large data). Hence this solution. Thought to share this as it might come in handy for others.

I had the same issue in a windows machine and I noticed that for some reason it didn't work in git bash, but it was working in power shell

Just in case it may help people having this issue while using nodejs apps that produce heavy logging, a colleague solved this issue by piping the standard output(s) to a file.

If you are trying to launch not node itself, but some other soft, for example webpack you can use the environment variable and cross-env package:
$ cross-env NODE_OPTIONS='--max-old-space-size=4096' \
webpack --progress --config build/webpack.config.dev.js

For angular project bundling, I've added the below line to my pakage.json file in the scripts section.
"build-prod": "node --max_old_space_size=5120 ./node_modules/#angular/cli/bin/ng build --prod --base-href /"
Now, to bundle my code, I use npm run build-prod instead of ng build --requiredFlagsHere
hope this helps!

If any of the given answers are not working for you, check your installed node if it compatible (i.e 32bit or 64bit) to your system. Usually this type of error occurs because of incompatible node and OS versions and terminal/system will not tell you about that but will keep you giving out of memory error.

None of all these every single answers worked for me (I didn't try to update npm tho).
Here's what worked: My program was using two arrays. One that was parsed on JSON, the other that was generated from datas on the first one. Just before the second loop, I just had to set my first JSON parsed array back to [].
That way a loooooot of memory is freed, allowing the program to continue execution without failing memory allocation at some point.
Cheers !

You can fix a "heap out of memory" error in Node.js by below approaches.
Increase the amount of memory allocated to the Node.js process by using the --max-old-space-size flag when starting the application. For example, you can increase the limit to 4GB by running node --max-old-space-size=4096 index.js.
Use a memory leak detection tool, such as the Node.js heap dump module, to identify and fix memory leaks in your application. You can also use the node inspector and use chrome://inspect to check memory usage.
Optimize your code to reduce the amount of memory needed. This might involve reducing the size of data structures, reusing objects instead of creating new ones, or using more efficient algorithms.
Use a garbage collector (GC) algorithm to manage memory automatically. Node.js uses the V8 engine's garbage collector by default, but you can also use other GC algorithms such as the Garbage Collection in Node.js
Use a containerization technology like Docker which limits the amount of memory available to the container.
Use a process manager like pm2 which allows to automatically restart the node application if it goes out of memory.

how to prevent mocha from exiting process with status 1

I have written a simple node.js application and now I want to add some tests. For now I have only some example Tests to test my Gitlab-CI, SonarQube and Mocha, which i am using for testing.
Now my problem is, that I want to parse the results from mocha (reporter is the sonar-mocha-reporter). My problem is that mocha exits the process with status 1 if a test is failing. That means gitlab-ci is breaking the build and will not run to the end. So i can not parse the results like it should.
Is there a way to configure mocha to not break my build so that it only saves the results in this xml file?
I am starting mocha with:
./node_modules/.bin/mocha -R mocha-sonar-reporter --recursive --no-exit
and in my package.json i have the configuration:
"config": {
"mocha-sonar-reporter": {
"outputfile": "build/reports/tests/TEST-mocha.xml"
}
},

Perhaps can you just do:
./node_modules/.bin/mocha || true
If it fails, it will then return true, and be successful.

Add parameter silent to command line. For example:
npm run test --silent

Cloud 9 and Grunt.js

I'm running grunt.js on Cloud9. Most everything is working correctly, except when I try to set this option:
'watch: {
options: {livereload:true},'
If I add that, the terminal states: 'Fatal error: listen EACCES'
I'm guessing I need to use the sudo command to run that and since c9 doesn't let you run sudo, the command fails.
But why is livereload a feature that requires permission? And is there any way around it?

Where do npm background scripts go?

I have a program which relies on another program being run so I added this build command to my package.json file
"scripts": {
"start": "brunch watch --server",
"build": "coffee server/modules/events/book_server.coffee &"
}
so before I run my main script with npm start I run npm run-script build which makes my main script work, however when I quit my main script and then look for background processes with bg I get the message
> -bash: bg: current: no such job
so I decided to run npm run-script build again however the previous process must still have been running because I got the error message
events.js:66
throw arguments[1]; // Unhandled 'error' event
^
Error: listen EADDRINUSE
at errnoException (net.js:776:11)
at Server._listen2._connectionKey (net.js:917:26)
at process.startup.processNextTick.process._tickCallback (node.js:244:9)
and when I tried to run my main program again I got the error
> TypeError: Cannot read property 'port' of null
My question is, where are these background scripts?
So far I have looked in all the obvious places including package.json's directory the directory for book_server.coffee and in node_modules but with no luck.

So the background processes go into the background just running inside the OS but not attached to your shell's tty. To find them, use jobs -l or the ps command with something like ps -ef. You can use grep to filter the output, but what you need to find is the process ID (PID) of your build process so you can stop it with kill <pid>. You may also want to read up on pgrep and pkill which are handy for this process.
Note that in your example you use bg when it's not appropriate. bg is for this sequence: 1. start a job in your shell's foreground, 2. suspend that job with CTRL-Z, 3. use bg to tell the shell "allow this job to continue executing, but detached from my tty in the background". (again, jobs is what you are looking for here).
For the bigger picture, there's no need or benefit of running that coffee command in the background as it is just a simple compliation step that should take on the order of a few milliseconds.
For an amazingly-detailed "reread every year" level of depth, check out The TTY demystified.