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-rw-r--r--examples/read.lua70
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diff --git a/examples/read.lua b/examples/read.lua
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+local sys = require "system"
+
+print [[
+
+This example shows how to do a non-blocking read from the cli.
+
+]]
+
+-- setup Windows console to handle ANSI processing
+local of_in = sys.getconsoleflags(io.stdin)
+local of_out = sys.getconsoleflags(io.stdout)
+sys.setconsoleflags(io.stdout, sys.getconsoleflags(io.stdout) + sys.COF_VIRTUAL_TERMINAL_PROCESSING)
+sys.setconsoleflags(io.stdin, sys.getconsoleflags(io.stdin) + sys.CIF_VIRTUAL_TERMINAL_INPUT)
+
+-- setup Posix terminal to use non-blocking mode, and disable line-mode
+local of_attr = sys.tcgetattr(io.stdin)
+local of_block = sys.getnonblock(io.stdin)
+sys.setnonblock(io.stdin, true)
+sys.tcsetattr(io.stdin, sys.TCSANOW, {
+ lflag = of_attr.lflag - sys.L_ICANON - sys.L_ECHO, -- disable canonical mode and echo
+})
+
+-- cursor sequences
+local get_cursor_pos = "\27[6n"
+
+
+
+print("Press a key, or 'A' to get cursor position, 'ESC' to exit")
+while true do
+ local key, keytype
+
+ -- wait for a key
+ while not key do
+ key, keytype = sys.readansi(math.huge)
+ end
+
+ if key == "A" then io.write(get_cursor_pos); io.flush() end
+
+ -- check if we got a key or ANSI sequence
+ if keytype == "char" then
+ -- just a key
+ local b = key:byte()
+ if b < 32 then
+ key = "." -- replace control characters with a simple "." to not mess up the screen
+ end
+
+ print("you pressed: " .. key .. " (" .. b .. ")")
+ if b == 27 then
+ print("Escape pressed, exiting")
+ break
+ end
+
+ elseif keytype == "ansi" then
+ -- we got an ANSI sequence
+ local seq = { key:byte(1, #key) }
+ print("ANSI sequence received: " .. key:sub(2,-1), "(bytes: " .. table.concat(seq, ", ")..")")
+
+ else
+ print("unknown key type received: " .. tostring(keytype))
+ end
+end
+
+
+
+-- Clean up afterwards
+sys.setnonblock(io.stdin, false)
+sys.setconsoleflags(io.stdout, of_out)
+sys.setconsoleflags(io.stdin, of_in)
+sys.tcsetattr(io.stdin, sys.TCSANOW, of_attr)
+sys.setnonblock(io.stdin, of_block)