tasks a-s

Task/Random-number-generator--device-/NetRexx/random-number-generator--device-.netrexx

@@ -0,0 +1,32 @@
+/* NetRexx */
+options replace format comments java crossref savelog symbols binary
+
+import java.math.BigInteger
+
+randomDevNameFile = File
+randomDevNameList = ['/dev/random', '/dev/urandom'] -- list of random data source devices
+randomDevIStream = InputStream
+do
+  loop dn = 0 to randomDevNameList.length - 1
+    randomDevNameFile = File(randomDevNameList[dn])
+    if randomDevNameFile.exists() then leave dn -- We're done! Use this device
+    randomDevNameFile = null -- ensure we don't use a non-existant device
+    end dn
+  if randomDevNameFile == null then signal FileNotFoundException('Cannot locate a random data source device on this system')
+
+  -- read 8 bytes from the random data source device, convert it into a BigInteger then display the result
+  randomBytes = byte[8]
+  randomDevIStream = BufferedInputStream(FileInputStream(randomDevNameFile))
+  randomDevIStream.read(randomBytes, 0, randomBytes.length)
+  randomDevIStream.close()
+  randomNum = BigInteger(randomBytes)
+  say Rexx(randomNum.longValue()).right(24) '0x'Rexx(Long.toHexString(randomNum.longValue())).right(16, 0)
+catch ex = IOException
+  ex.printStackTrace()
+end
+return
+
+/*
+To run the program in a loop 10 times from a bash shell prompt use:
+for ((i=0; i<10; ++i)); do java <program_name>; done # Shell loop to run the command 10 times
+*/