made io.stderr an extra stream that applies a red foreground color (if possible); writing errors to stderr in programs; quoting and escaping vars in list displayed by set.lua

src/main/resources/assets/opencomputers/lua/component/internet/bin/pastebin.lua

@@ -6,7 +6,7 @@ local internet = require("internet")
 local shell = require("shell")
 
 if not component.isAvailable("internet") then
-  io.write("This program requires an internet card to run.")
+  io.stderr:write("This program requires an internet card to run.")
   return
 end
 
@@ -16,7 +16,7 @@ local args, options = shell.parse(...)
 local function get(pasteId, filename)
   local f, reason = io.open(filename, "w")
   if not f then
-    io.write("Failed opening file for writing: ", reason)
+    io.stderr:write("Failed opening file for writing: ", reason)
     return
   end
 
@@ -37,7 +37,7 @@ local function get(pasteId, filename)
   else
     f:close()
     fs.remove(filename)
-    io.write("HTTP request failed: ", response, "\n")
+    io.stderr:write("HTTP request failed: ", response, "\n")
   end
 end
 
@@ -61,7 +61,7 @@ function run(pasteId, ...)
 
   local success, reason = shell.execute(tmpFile, nil, ...)
   if not success then
-    io.write(reason)
+    io.stderr:write(reason)
   end
   fs.remove(tmpFile)
 end
@@ -73,14 +73,14 @@ function put(path)
   if configFile then
     local result, reason = pcall(configFile)
     if not result then
-      io.write("Failed loading config: ", reason)
+      io.stderr:write("Failed loading config: ", reason)
     end
   end
   config.key = config.key or "fd92bd40a84c127eeb6804b146793c97"
   local file, reason = io.open(path, "r")
 
   if not file then
-    io.write("Failed opening file for reading: ", reason)
+    io.stderr:write("Failed opening file for reading: ", reason)
     return
   end
 
@@ -112,7 +112,8 @@ function put(path)
       io.write('Run "pastebin get ', pasteId, '" to download anywhere.')
     end
   else
-    io.write("failed: ", response)
+    io.write("failed.\n")
+    io.stderr:write(response)
   end
 end
 
@@ -127,7 +128,7 @@ elseif command == "get" then
     local path = shell.resolve(args[3])
     if fs.exists(path) then
       if not options.f or not os.remove(path) then
-        io.write("file already exists")
+        io.stderr:write("file already exists")
         return
       end
     end

src/main/resources/assets/opencomputers/lua/component/internet/bin/wget.lua

@@ -5,7 +5,7 @@ local shell = require("shell")
 local text = require("text")
 
 if not component.isAvailable("internet") then
-  io.write("This program requires an internet card to run.")
+  io.stderr:write("This program requires an internet card to run.")
   return
 end
 
@@ -33,21 +33,21 @@ if not filename then
 end
 filename = text.trim(filename)
 if filename == "" then
-  io.write("could not infer filename, please specify one")
+  io.stderr:write("could not infer filename, please specify one")
   return
 end
 filename = shell.resolve(filename)
 
 if fs.exists(filename) then
   if not options.f or not os.remove(filename) then
-    io.write("file already exists")
+    io.stderr:write("file already exists")
     return
   end
 end
 
 local f, reason = io.open(filename, "wb")
 if not f then
-  io.write("Failed opening file for writing: ", reason)
+  io.stderr:write("failed opening file for writing: ", reason)
   return
 end
 
@@ -68,7 +68,10 @@ if result then
     io.write("Saved data to ", filename, "\n")
   end
 else
+  if not options.q then
+    io.write("failed.\n")
+  end
   f:close()
   fs.remove(filename)
-  io.write("HTTP request failed: ", response, "\n")
+  io.stderr:write("HTTP request failed: ", response, "\n")
 end

src/main/resources/assets/opencomputers/lua/component/robot/bin/dig.lua

@@ -5,7 +5,8 @@ local shell = require("shell")
 local sides = require("sides")
 
 if not computer.isRobot() then
-  error("can only run on robots", 0)
+  io.stderr:write("can only run on robots")
+  return
 end
 
 local args, options = shell.parse(...)
@@ -17,7 +18,8 @@ end
 
 local size = tonumber(args[1])
 if not size then
-  error("invalid size", 0)
+  io.stderr:write("invalid size")
+  return
 end
 
 local r = component.computer

src/main/resources/assets/opencomputers/lua/rom/bin/alias.lua

@@ -11,7 +11,7 @@ elseif #args == 1 then
   if value then
     io.write(value)
   else
-    io.write("no such alias")
+    io.stderr:write("no such alias")
   end
 else
   shell.setAlias(args[1], args[2])

src/main/resources/assets/opencomputers/lua/rom/bin/cat.lua

@@ -12,7 +12,7 @@ else
   for i = 1, #args do
     local file, reason = io.open(shell.resolve(args[i]))
     if not file then
-      io.write(reason)
+      io.stderr:write(reason)
       return
     end
     repeat

src/main/resources/assets/opencomputers/lua/rom/bin/cd.lua

@@ -6,6 +6,6 @@ if #args == 0 then
 else
   local result, reason = shell.setWorkingDirectory(shell.resolve(args[1]))
   if not result then
-    io.write(reason)
+    io.stderr:write(reason)
   end
 end

src/main/resources/assets/opencomputers/lua/rom/bin/cp.lua

@@ -14,9 +14,10 @@ if fs.isDirectory(to) then
   to = to .. "/" .. fs.name(from)
 end
 if fs.exists(to) and not options.f then
-  error("target file exists")
+  io.stderr:write("target file exists")
+  return
 end
 local result, reason = fs.copy(from, to)
 if not result then
-  io.write(reason)
+  io.stderr:write(reason)
 end

src/main/resources/assets/opencomputers/lua/rom/bin/df.lua

@@ -12,7 +12,7 @@ else
   for i = 1, #args do
     local proxy, path = fs.get(args[i])
     if not proxy then
-      io.write(args[i], ": no such file or directory\n")
+      io.stderr:write(args[i], ": no such file or directory\n")
     else
       mounts[path] = proxy
     end

src/main/resources/assets/opencomputers/lua/rom/bin/edit.lua

@@ -22,7 +22,7 @@ local filename = shell.resolve(args[1])
 local readonly = options.r or fs.get(filename) == nil or fs.get(filename).isReadOnly()
 
 if fs.isDirectory(filename) or readonly and not fs.exists(filename) then
-  io.write("file not found")
+  io.stderr:write("file not found")
   return
 end
 

src/main/resources/assets/opencomputers/lua/rom/bin/label.lua

@@ -15,15 +15,15 @@ else
   proxy, reaons = fs.get(args[1])
 end
 if not proxy then
-  io.write(reason)
+  io.stderr:write(reason)
   return
 end
 
 if #args < 2 then
-  io.write(proxy.getLabel() or "no label")
+  io.stderr:write(proxy.getLabel() or "no label")
 else
   local result, reason = proxy.setLabel(args[2])
   if not result then
-    io.write(reason or "could not set label")
+    io.stderr:write(reason or "could not set label")
   end
 end

src/main/resources/assets/opencomputers/lua/rom/bin/ln.lua

@@ -18,5 +18,5 @@ end
 
 local result, reason = fs.link(target, linkpath)
 if not result then
-  io.write(reason)
+  io.stderr:write(reason)
 end

src/main/resources/assets/opencomputers/lua/rom/bin/lua.lua

@@ -46,7 +46,7 @@ while term.isAvailable() do
       if type(result[2]) == "table" and result[2].reason == "terminated" then
         os.exit(result[2].code)
       end
-      io.write(tostring(result[2]), "\n")
+      io.stderr:write(tostring(result[2]), "\n")
     else
       for i = 2, result.n do
         io.write(text.serialize(result[i], true), "\t")
@@ -56,6 +56,6 @@ while term.isAvailable() do
       end
     end
   else
-    io.write(reason, "\n")
+    io.stderr:write(reason, "\n")
   end
 end

src/main/resources/assets/opencomputers/lua/rom/bin/man.lua

@@ -16,4 +16,4 @@ for path in string.gmatch(os.getenv("MANPATH"), "[^:]+") do
     os.exit()
   end
 end
-io.write("No manual entry for " .. topic)
+io.stderr:write("No manual entry for " .. topic)

src/main/resources/assets/opencomputers/lua/rom/bin/mkdir.lua

@@ -18,6 +18,6 @@ for i = 1, #args do
         reason = "unknown reason"
       end
     end
-    io.write(path, ": ", reason, "\n")
+    io.stderr:write(path, ": ", reason, "\n")
   end
 end

src/main/resources/assets/opencomputers/lua/rom/bin/more.lua

@@ -12,7 +12,7 @@ end
 
 local file, reason = io.open(shell.resolve(args[1]))
 if not file then
-  io.write(reason)
+  io.stderr:write(reason)
   return
 end
 

src/main/resources/assets/opencomputers/lua/rom/bin/mount.lua

@@ -18,11 +18,11 @@ end
 
 local proxy, reason = fs.proxy(args[1])
 if not proxy then
-  io.write(reason)
+  io.stderr:write(reason)
   return
 end
 
 local result, reason = fs.mount(proxy, shell.resolve(args[2]))
 if not result then
-  io.write(reason)
+  io.stderr:write(reason)
 end

src/main/resources/assets/opencomputers/lua/rom/bin/mv.lua

@@ -15,11 +15,11 @@ if fs.isDirectory(to) then
 end
 if fs.exists(to) then
   if not options.f then
-    io.write("target file exists")
+    io.stderr:write("target file exists")
   end
   fs.remove(to)
 end
 local result, reason = os.rename(from, to)
 if not result then
-  io.write(reason or "unknown error")
+  io.stderr:write(reason or "unknown error")
 end

src/main/resources/assets/opencomputers/lua/rom/bin/primary.lua

@@ -13,7 +13,7 @@ local componentType = args[1]
 if #args > 1 then
   local address = args[2]
   if not component.get(address) then
-    io.write("no component with this address")
+    io.stderr:write("no component with this address")
     return
   else
     component.setPrimary(componentType, address)
@@ -23,5 +23,5 @@ end
 if component.isAvailable(componentType) then
   io.write(component.getPrimary(componentType).address)
 else
-  io.write("no primary component for this type")
+  io.stderr:write("no primary component for this type")
 end

src/main/resources/assets/opencomputers/lua/rom/bin/redstone.lua

@@ -3,6 +3,10 @@ local component = require("component")
 local shell = require("shell")
 local sides = require("sides")
 
+if not component.isAvailable("redstone") then
+  io.stderr:write("This program requires a redstone card or redstone I/O block.")
+  return
+end
 local rs = component.redstone
 
 local args, options = shell.parse(...)
@@ -17,7 +21,8 @@ end
 
 local side = sides[args[1]]
 if not side then
-  error("Invalid side.")
+  io.stderr:write("invalid side")
+  return
 end
 if type(side) == "string" then
   side = sides[side]
@@ -25,11 +30,13 @@ end
 
 if options.b then
   if not rs.setBundledOutput then
-    error("Bundled redstone not available.")
+    io.stderr:write("bundled redstone not available")
+    return
   end
   local color = colors[args[2]]
   if not color then
-    error("Invalid color.")
+    io.stderr:write("invalid color")
+    return
   end
   if type(color) == "string" then
     color = colors[color]

src/main/resources/assets/opencomputers/lua/rom/bin/resolution.lua

@@ -17,12 +17,13 @@ end
 local w = tonumber(args[1])
 local h = tonumber(args[2])
 if not w or not h then
-  io.write("invalid width or height")
+  io.stderr:write("invalid width or height")
   return
 end
 
 local result, reason = component.gpu.setResolution(w, h)
 if not result then
-  io.write(reason)
+  io.stderr:write(reason)
+  return
 end
 term.clear()

src/main/resources/assets/opencomputers/lua/rom/bin/rm.lua

@@ -9,6 +9,6 @@ end
 for i = 1, #args do
   local path = shell.resolve(args[i])
   if not os.remove(path) then
-    io.write(path, ": no such file, or permission denied\n")
+    io.stderr:write(path, ": no such file, or permission denied\n")
   end
 end

src/main/resources/assets/opencomputers/lua/rom/bin/set.lua

@@ -2,7 +2,7 @@ local args = {...}
 
 if #args < 1 then
   for k,v in pairs(os.getenv()) do
-    io.write(k..'='..v..'\n')
+    io.write(k, "='", string.gsub(v, "'", [['"'"']]), "'\n")
   end
 else
   local count = 1

src/main/resources/assets/opencomputers/lua/rom/bin/sh.lua

@@ -9,7 +9,7 @@ local args, options = shell.parse(...)
 local history = {}
 
 if options.v or not shell.running(2) then
-  print(_OSVERSION .. " (" .. math.floor(computer.totalMemory() / 1024) .. "k RAM)")
+  io.write(_OSVERSION .. " (" .. math.floor(computer.totalMemory() / 1024) .. "k RAM)\n")
 end
 
 while true do
@@ -19,7 +19,7 @@ while true do
     end
     term.clear()
     if options.v then
-      print(_OSVERSION .. " (" .. math.floor(computer.totalMemory() / 1024) .. "k RAM)")
+      io.write(_OSVERSION .. " (" .. math.floor(computer.totalMemory() / 1024) .. "k RAM)\n")
     end
   end
   while term.isAvailable() do
@@ -28,7 +28,7 @@ while true do
     component.gpu.setForeground(foreground)
     local command = term.read(history)
     if not command then
-      print("exit")
+      io.write("exit\n")
       return -- eof
     end
     while #history > 10 do
@@ -40,10 +40,10 @@ while true do
     elseif command ~= "" then
       local result, reason = os.execute(command)
       if not result then
-        print(reason)
+        io.stderr:write(reason .. "\n")
       elseif term.getCursor() > 1 then
-        print()
+        io.write("\n")
       end
     end
   end
-end
+end

src/main/resources/assets/opencomputers/lua/rom/bin/umount.lua

@@ -21,16 +21,16 @@ else
   if proxy then
     proxy = reason -- = path
     if proxy ~= path then
-      io.write("not a mount point")
+      io.stderr:write("not a mount point")
       return
     end
   end
 end
 if not proxy then
-  io.write(reason)
+  io.stderr:write(reason)
   return
 end
 
 if not fs.umount(proxy) then
-  io.write("nothing to unmount here")
+  io.stderr:write("nothing to unmount here")
 end

src/main/resources/assets/opencomputers/lua/rom/bin/unalias.lua

@@ -8,7 +8,7 @@ end
 
 local result = shell.getAlias(args[1])
 if not result then
-  io.write("no such alias")
+  io.stderr:write("no such alias")
 else
   shell.setAlias(args[1], nil)
   io.write("alias removed: ", args[1], " -> ", result)

src/main/resources/assets/opencomputers/lua/rom/bin/unset.lua

@@ -1,9 +1,9 @@
 local args = {...}
 
 if #args < 1 then
-  print "You have to specify which arguments to unset!"
+  print("Usage: unset <varname>[ <varname2> [...]]")
 else
   for _, k in ipairs(args) do
     os.setenv(k, nil)
   end
-end  
+end

src/main/resources/assets/opencomputers/lua/rom/bin/useradd.lua

@@ -9,5 +9,5 @@ end
 
 local result, reason = computer.addUser(args[1])
 if not result then
-  io.write(reason)
+  io.stderr:write(reason)
 end

src/main/resources/assets/opencomputers/lua/rom/bin/userdel.lua

@@ -8,5 +8,5 @@ if #args < 1 then
 end
 
 if not computer.removeUser(args[1]) then
-  io.write("no such user")
+  io.stderr:write("no such user")
 end

src/main/resources/assets/opencomputers/lua/rom/bin/which.lua

@@ -16,6 +16,6 @@ for i = 1, #args do
   if result then
     io.write(result, "\n")
   else
-    io.write(args[i], ": ", reason, "\n")
+    io.stderr:write(args[i], ": ", reason, "\n")
   end
 end

src/main/resources/assets/opencomputers/lua/rom/boot/01_io.lua

@@ -3,6 +3,7 @@ local term = require("term")
 
 local stdinStream = {handle="stdin"}
 local stdoutStream = {handle="stdout"}
+local stderrStream = {handle="stderr"}
 local stdinHistory = {}
 
 local function badFileDescriptor()
@@ -13,6 +14,7 @@ function stdinStream:close()
   return nil, "cannot close standard file"
 end
 stdoutStream.close = stdinStream.close
+stderrStream.close = stdinStream.close
 
 function stdinStream:read(n)
   local result = term.read(stdinHistory)
@@ -27,16 +29,32 @@ function stdoutStream:write(str)
   return self
 end
 
+function stderrStream:write(str)
+  local component = require("component")
+  if component.isAvailable("gpu") and component.gpu.getDepth() > 1 then
+    local foreground = component.gpu.getForeground()
+    component.gpu.setForeground(0xFF0000)
+    term.write(str, true)
+    component.gpu.setForeground(foreground)
+  else
+    term.write(str, true)
+  end
+  return self
+end
+
 stdinStream.seek = badFileDescriptor
 stdinStream.write = badFileDescriptor
 stdoutStream.read = badFileDescriptor
 stdoutStream.seek = badFileDescriptor
+stderrStream.read = badFileDescriptor
+stderrStream.seek = badFileDescriptor
 
 io.stdin = buffer.new("r", stdinStream)
 io.stdout = buffer.new("w", stdoutStream)
-io.stderr = io.stdout
+io.stderr = buffer.new("w", stderrStream)
 
 io.stdout:setvbuf("no")
+io.stderr:setvbuf("no")
 
 io.input(io.stdin)
 io.output(io.stdout)