add iterm2 shell integration

.iterm2/it2getvar

@@ -0,0 +1,99 @@
+#!/bin/bash
+
+function ctrl_c() {
+  stty "$saved_stty"
+  exit 1
+}
+
+# tmux requires unrecognized OSC sequences to be wrapped with DCS tmux;
+# <sequence> ST, and for all ESCs in <sequence> to be replaced with ESC ESC. It
+# only accepts ESC backslash for ST.
+function print_osc() {
+    if [[ $TERM == screen* ]] ; then printf "\033Ptmux;\033\033]"
+    else
+        printf "\033]" >& 2
+    fi
+}
+
+# More of the tmux workaround described above.
+function print_st() {
+    if [[ $TERM == screen* ]] ; then
+        printf "\a\033\\" >& 2
+    else
+        printf "\a" >& 2
+    fi
+}
+
+function show_help() {
+    echo "Usage:" 1>& 2
+    echo "   $(basename $0) name" 1>& 2
+}
+
+# Read some bytes from stdin. Pass the number of bytes to read as the first argument.
+function read_bytes() {
+  numbytes=$1
+  dd bs=1 count=$numbytes 2>/dev/null
+}
+
+# read_until c
+# Returns bytes read from stdin up to but not including the fist one equal to c
+function read_until() {
+  result=""
+  while :
+  do
+    b=$(read_bytes 1)
+    if [[ $b == $1 ]]
+    then
+      echo "$result"
+      return
+    fi
+    result="$result$b"
+  done
+}
+
+## Main
+if [[ $# != 1 ]]
+then
+  show_help
+  exit 1
+fi
+
+if ! test -t 1
+then
+  echo "Standard error not a terminal"
+  exit 1
+fi
+
+# Save the tty's state.
+saved_stty=$(stty -g)
+
+# Trap ^C to fix the tty.
+trap ctrl_c INT
+
+# Enter raw mode and turn off echo so the terminal and I can chat quietly.
+stty -echo -icanon raw
+
+print_osc
+printf "1337;ReportVariable=%s" "$(printf "%s" "$1" | base64)" >& 2
+print_st
+
+VERSION=$(base64 --version 2>&1)
+if [[ "$VERSION" =~ fourmilab ]]; then
+  BASE64ARG=-d
+elif [[ "$VERSION" =~ GNU ]]; then
+  BASE64ARG=-di
+else
+  BASE64ARG=-D
+fi
+
+ignore=$(read_bytes 1)
+name=$(read_until )
+re='^]1337;ReportVariable=(.*)'
+if [[ $name =~ $re ]]
+then
+  printf "%s" $(base64 $BASE64ARG <<< ${BASH_REMATCH[1]})
+  exit 0
+else
+  exit 1
+fi
+