Capture node.js crash reason

I have a script written in node.js, it uses ‘net’ library and communicates with distant service over tcp. This script is started using ‘node script.js >> log.txt’ command and everything in that script that is logged using console.log() function gets written to log.txt but sometimes script dies and I cannot find a reason and nothing gets logged in log.txt around the time script crashed.

How can I capture crash reason?

Here is Solutions:

We have many solutions to this problem, But we recommend you to use the first solution because it is tested & true solution that will 100% work for you.

Solution 1

Couldn’t you listen to uncaughtException event. Something along the lines of =>

process.on('uncaughtException', function (err) {
  console.log('Caught exception: ' + err);

P.S: after that you are adviced to restart process according to this article from Felix Geisendörfer

Solution 2

It’s much easier to capture exceptions by splitting stdout and stderr. Like so:

node script.js 1> log.out 2> err.out

By default, node logs normal output to stdout, which I believe you are capturing with >>.

As noted in the comments, a segmentation fault is a signal put to stderr by the shell, not necessarily your program. See this unix.stackexchange answer for other options.

Note: Use and implement solution 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from or, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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