Use tr instead of sed to unDOSify the config file, so it works on Macs.

user_tools/linux/recovery.sh

 #!/bin/sh
 #
 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 #
 # This attempts to guide linux users through the process of putting a recovery
 # image onto a removeable USB drive.
 #
 # We may not need root privileges if we have the right permissions.
@@ skipping 86 matching lines @@
 #   FETCH          = name of utility used to download files from the web
 #   CHECK          = command to invoke to generate checksums on a file
 #   CHECKTYPE      = type of checksum generated
 #
 require_utils() {
   local external
   local errors
   local tool
   local tmp
 
-  external='cat cut dd grep ls mkdir mount readlink sed sync umount unzip wc'
+  external='cat cut dd grep ls mkdir mount readlink sed sync tr umount unzip wc'
   if [ -z "$WORKDIR" ]; then
     external="$external mktemp"
   fi
   errors=
 
   for tool in $external ; do
     if ! type "$tool" >/dev/null 2>&1 ; then
       warn "ERROR: need \"$tool\""
       errors=yes
     fi
@@ skipping 533 matching lines @@
 cd "$WORKDIR"
 warn "Working in $WORKDIR/"
 rm -f "$debug"
 
 # Download the config file to see what choices we have.
 warn "Downloading config file from $CONFIGURL"
 fetch_url "$CONFIGURL" "$tmpfile" || \
   gfatal "Unable to download the config file"
 
 # Un-DOS-ify the config file and separate the version info from the images
-sed 's/\r//g' "$tmpfile" | grep '^recovery_tool' > "$version"
-sed 's/\r//g' "$tmpfile" | grep -v '^#' | grep -v '^recovery_tool' > "$config"
+tr -d '\015' < "$tmpfile" | grep '^recovery_tool' > "$version"
+tr -d '\015' < "$tmpfile" | grep -v '^#' | grep -v '^recovery_tool' > "$config"
 # Add one empty line to the config file to terminate the last stanza
 echo >> "$config"
 
 # Make sure that the config file version matches this script version
 tmp=$(grep '^recovery_tool_version=' "$version") || \
   gfatal "The config file doesn't contain a version string."
 filevers=${tmp#*=}
 if [ "$filevers" != "$MYVERSION" ]; then
   tmp=$(grep '^recovery_tool_update=' "$version");
   msg=${tmp#*=}
@@ skipping 45 matching lines @@
   quit
 fi
 echo "
 
 Installing the recovery image
 
 "
 
 # Unmount anything on that device.
 echo "unmounting..."
-for tmp in $(mount | grep ^"/dev/${user_choice}" | sed 's/[ \t].*//'); do
+for tmp in $(mount | grep ^"/dev/${user_choice}" | cut -d' ' -f1); do
   umount $tmp || ufatal "Unable to unmount $tmp."
 done
 
 # Write it.
 echo "copying... (this may take several minutes)"
 dd of=/dev/${user_choice} if="$image_file" ||
   ufatal "Unable to write the image."
 sync
 
 echo "
 
 Done. Remove the USB drive and insert it in your Chrome OS netbook.
 
 "
 
 exit 0