dehydrate.sh

@@ -3,9 +3,9 @@ set -eo pipefail
 
 image="$1"; [ -z "$1" ] && { echo "No image file specified!" >&2; exit 1; }
 mfile="$2"; [ -z "$2" ] && { echo "No mapfile specified!"    >&2; exit 1; }
-[ -z $3 ] && [ -t 1 ] && { echo "The output of this script is unsafe for raw display." >&2
-                           exit 1; } \
-		      || ofile=${3:-/dev/stdout}
+[ -z "$3" -a -t 1 ] && { echo "The output of this script is unsafe for raw display." >&2
+                         exit 1; } \
+		    || ofile=${3:-/dev/stdout}
 
 BLOCKSIZE=`sed -nE 's/^#BLOCKSIZE=([0-9]+)$/\1/p' "$mfile"`
 [ -z "$BLOCKSIZE" ] && { echo "Mapfile does not specify blocksize!" >&2; exit 1; }