tested in Kubuntu v20.04

fetch_0ad_RevisionNr_and_write_sh_script.kt

//# here SH-file is autogenerated by a kotlin script.
//# it reads revision number from website, gets it, and starts 0ad
//# works in kubuntu v 20.04

import java.io.File
import java.lang.Exception
import java.net.URL
import java.net.URLConnection
import java.util.*

fun main(args: Array<String>) {
    val userHome = System.getProperty("user.home")
    val path = System.getProperty(userHome)
    val scriptPre = """
# this file is autogenerated by a kotlin script.
# it reads revision number from website, gets it, and starts 0ad
# works in kubuntu v 20.04
# maybe check here manuel: https://wildfiregames.com/forum/topic/36379-release-candidate-2-alpha-24-x%C5%A1ay%C4%81r%C5%A1%C4%81
cd ~/svn;
svn up -r """
val scriptPost = """; # <== sets working back to this revision number
cd ~/svn/0ad/build/workspaces ; ./update-workspaces.sh -j13
cd ~/svn/0ad/build/workspaces/gcc ; make -j13
~/svn/0ad/binaries/system/pyrogenesis &
"""
    val regex = """(?<preSting>Revision[ ]*:[ ]*[rP]*)(?<revNumber>\d+)""".toRegex() // Revision: rP24928
    var content: String? = null
    var connection: URLConnection? = null
    try {
        connection = URL("https://wildfiregames.com/forum/topic/36379-release-candidate-2-alpha-24-x%C5%A1ay%C4%81r%C5%A1%C4%81").openConnection()
        val scanner = Scanner(connection.getInputStream())
        scanner.useDelimiter("\\Z")
        content = scanner.next()
        var matchResult = regex.find(content)
        val (preSting, revNumber) = matchResult!!.destructured
        if (matchResult != null) {
            matchResult = matchResult.next()
            println(matchResult!!.value)
            println(matchResult!!.groupValues)
            println("revNumber= $revNumber" )
            scanner.close()

            val scriptAll = scriptPre + revNumber + scriptPost
            File("$userHome/sh-scripts/0ad-get-Revision-and-start.sh").bufferedWriter().use { out ->
                out.write(scriptAll)
            }
        } // next returns null when there are no more matches.
        scanner.close()
    } catch (ex: Exception) {
        ex.printStackTrace()
    }
}