Merge pull request #21 from lunarmodules/terminal

1 files changed, 40 insertions, 0 deletions

diff --git a/examples/compat.lua b/examples/compat.lua
new file mode 100644
index 0000000..c712105
--- /dev/null
+++ b/examples/compat.lua
@@ -0,0 +1,40 @@
+-- This example shows how to remove platform differences to create a
+-- cross-platform level playing field.
+
+local sys = require "system"
+
+
+
+if sys.windows then
+  -- Windows holds multiple copies of environment variables, to ensure `getenv`
+  -- returns what `setenv` sets we need to use the `system.getenv` instead of
+  -- `os.getenv`.
+  os.getenv = sys.getenv  -- luacheck: ignore
+
+  -- Set console output to UTF-8 encoding.
+  sys.setconsoleoutputcp(sys.CODEPAGE_UTF8)
+
+  -- Set up the terminal to handle ANSI escape sequences on Windows.
+  if sys.isatty(io.stdout) then
+    sys.setconsoleflags(io.stdout, sys.getconsoleflags(io.stdout) + sys.COF_VIRTUAL_TERMINAL_PROCESSING)
+  end
+  if sys.isatty(io.stderr) then
+    sys.setconsoleflags(io.stderr, sys.getconsoleflags(io.stderr) + sys.COF_VIRTUAL_TERMINAL_PROCESSING)
+  end
+  if sys.isatty(io.stdin) then
+    sys.setconsoleflags(io.stdin, sys.getconsoleflags(io.stdout) + sys.ENABLE_VIRTUAL_TERMINAL_INPUT)
+  end
+
+
+else
+  -- On Posix, one can set a variable to an empty string, but on Windows, this
+  -- will remove the variable from the environment. To make this consistent
+  -- across platforms, we will remove the variable from the environment if the
+  -- value is an empty string.
+  local old_setenv = sys.setenv
+  function sys.setenv(name, value)
+    if value == "" then value = nil end
+    return old_setenv(name, value)
+  end
+end
+