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I'm writing some node.js scripts to kick off a child process. Code snippet is as below.
var spawn = require('child_process').spawn;
var child = spawn ('node', ['script.js'])
child.stdout.on('data',
function (data) {
logger.verbose('tail output: ' + JSON.stringify(data));
}
);
child.stderr.on('data',
function (data) {
logger.error('err data: ' + data);
}
);
Script runs well except that child process's stdout and stderr prints only numeric outputs:
Sample output:
108,34,44,34,105,110,99,114,101,97,109,101,110,116,97,108,95,112,111,108,108,105
How do I convert these numeric values to readable string?
Thanks.
999
Usually, Node. js allows single-threaded, non-blocking performance but running a single thread in a CPU cannot handle increasing workload hence the child_process module can be used to spawn child processes. The child processes communicate with each other using a built-in messaging system.
spawn() or child_process. spawnSync() . child_process. exec() : spawns a shell and runs a command within that shell, passing the stdout and stderr to a callback function when complete.
Spawn is useful when you want to make a continuous data transfer in binary/encoding format — e.g. transferring a 1 Gigabyte video, image, or log file. Fork is useful when you want to send individual messages — e.g. JSON or XML data messages.
If you've been using Node. js for a while, you've definitely run into streams. HTTP connections are streams, open files are streams; stdin, stdout, and stderr are all streams as well.
data is an array buffer. Call its toString method JSON.stringify(data.toString('utf8'))
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