Execute external command

Question

I do not know whether it is a Scala or Play! question. I want to execute some external command from my Play application, get the output from the command and show a report to user based on the command output. Can anyone help?

For example, when I enter my-command from shell it shows output like below, which I want to capture and show in web:

Id    Name   IP
====================
1     A      x.y.z.a
2     B      p.q.r.s

Please, do not worry about format and parsing of the output. Functionally, I am looking something like PHP exec. I know about java Runtime.getRuntime().exec("command") but is there any Scala/Play version to serve the purpose?

I thought of this idea: I need to clear the console, and well, `print("\u001b[2J")` doesn't work, it just moves the console forward over and over again when used; so I thought I would execute `clear` to clear the console without moving it! — RixTheTyrunt, Jun 21 '22 at 16:37

score 46 · Accepted Answer · edited May 17 '21 at 11:15

46

The method !! of the Scala process package does what you need, it executes the statement and captures the text output. For example:

import scala.sys.process._
val cmd = "uname -a" // Your command
val output = cmd.!! // Captures the output

edited May 17 '21 at 11:15

mrucci

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answered Apr 24 '13 at 15:16

Björn Jacobs

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[Handy documentation link](http://www.scala-lang.org/api/2.10.4/#scala.sys.process.package) – BeepDog Aug 11 '14 at 19:59

score 7 · Answer 2 · answered Apr 23 '13 at 06:50

7

scala> import scala.sys.process._
scala> Process("cat temp.txt")!

This assumes there is a temp file in your home directory. ! is for actual execution of the command. See scala.sys.process for more info.

answered Apr 23 '13 at 06:50

Jamil

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What does the `_` do in the import? – RixTheTyrunt Jun 21 '22 at 16:38
New method of clearing the screen: `(Process("clear")!)` or `(Process("cls")!)`! – RixTheTyrunt Jun 21 '22 at 16:42

score -1 · Answer 3 · answered Mar 26 '21 at 12:29

-1

You can use the Process library: for instance

import scala.sys.process.Process
Process("ls").!!

to get the list of files in the folder as a string. The !! get the output of the command

answered Mar 26 '21 at 12:29

Galuoises

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Execute external command

3 Answers3

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