# and see if it looks like that they all begin with the
# header field names...
sed -n -e '/^$/q' -e '/^[ ]/d' -e p "$1" |
- egrep -v '^[A-Za-z]+(-[A-Za-z]+)*:' >/dev/null ||
+ LC_ALL=C egrep -v '^[!-9;-~]+:' >/dev/null ||
patch_format=mbox
fi
} < "$1" || clean_abort