Add a function to aid usage of xclip

oh-my-zsh/lib/functions.zsh

@@ -30,3 +30,35 @@ function extract () {
         echo "\`$1' is not a valid file"
     fi
 }
+
+# a shortcut function to simplify usage of xclip
+clip() {
+  local _scs_col="\e[0;32m"; local _wrn_col='\e[1;31m'; local _trn_col='\e[0;33m'
+  # Check that xclip is installed.
+  if ! type xclip > /dev/null 2>&1; then
+    echo -e "$_wrn_col""You must have the 'xclip' program installed.\e[0m"
+  # Check user is not root (root doesn't have access to user xorg server)
+  elif [[ "$USER" == "root" ]]; then
+    echo -e "$_wrn_col""Must be regular user (not root) to copy a file to the clipboard.\e[0m"
+  else
+    # If no tty, data should be available on stdin
+    if ! [[ "$( tty )" == /dev/* ]]; then
+      input="$(< /dev/stdin)"
+    # Else, fetch input from params
+    else
+      input="$*"
+    fi
+    if [ -z "$input" ]; then  # If no input, print usage message.
+      echo "Copies params or stdin to the clipboard."
+      echo "Usage: clip STRING"
+      echo "       clip < FILE"
+    else
+      # Copy input to clipboard
+      echo -n "$input" | xclip -selection c
+      # Truncate text for status
+      if [ ${#input} -gt 80 ]; then input="$(echo $input | cut -c1-80)$_trn_col...\e[0m"; fi
+      # Print status.
+      echo -e "$_scs_col""Copied to clipboard:\e[0m $input"
+    fi
+  fi
+}