set jna.nosys to true programmatically

Ref sbt/io#110

.appveyor.yml

@@ -20,4 +20,4 @@ install:
   - SET PATH=C:\sbt\sbt\bin;%PATH%
   - SET SBT_OPTS=-XX:MaxPermSize=2g -Xmx4g -Dfile.encoding=UTF8
 test_script:
-  - sbt "-Djna.nosys=true" "scripted actions/*"
+  - sbt "scripted actions/*"

build.sbt

@@ -572,7 +572,7 @@ def otherRootSettings =
     scriptedUnpublished := scriptedUnpublishedTask.evaluated,
     scriptedSource := (sourceDirectory in sbtProj).value / "sbt-test",
     // scriptedPrescripted := { addSbtAlternateResolver _ },
-    scriptedLaunchOpts := List("-Xmx1500M", "-Xms512M", "-server", "-Djna.nosys=true"),
+    scriptedLaunchOpts := List("-Xmx1500M", "-Xms512M", "-server"),
     publishAll := { val _ = (publishLocal).all(ScopeFilter(inAnyProject)).value },
     publishLocalBinAll := { val _ = (publishLocalBin).all(ScopeFilter(inAnyProject)).value },
     aggregate in bintrayRelease := false

main/src/main/scala/sbt/Main.scala

@@ -128,6 +128,9 @@ object StandardMain {
   def initialState(configuration: xsbti.AppConfiguration,
                    initialDefinitions: Seq[Command],
                    preCommands: Seq[String]): State = {
+    // This is to workaround https://github.com/sbt/io/issues/110
+    sys.props.put("jna.nosys", "true")
+
     import BasicCommandStrings.isEarlyCommand
     val userCommands = configuration.arguments.map(_.trim)
     val (earlyCommands, normalCommands) = (preCommands ++ userCommands).partition(isEarlyCommand)