read-novar.sh

Shall高级编程

#!/bin/bash
# read-novar.sh

echo

# -------------------------- #
echo -n "Enter a value: "
read var
echo "\"var\" = "$var""
# Everything as expected here.
# -------------------------- #

echo

# ------------------------------------------------------------------- #
echo -n "Enter another value: "
read           #  No variable supplied for 'read', therefore...
               #+ Input to 'read' assigned to default variable, $REPLY.
var="$REPLY"
echo "\"var\" = "$var""
# This is equivalent to the first code block.
# ------------------------------------------------------------------- #

echo
echo "========================="
echo


#  This example is similar to the "reply.sh" script.
#  However, this one shows that $REPLY is available
#+ even after a 'read' to a variable in the conventional way.


# ================================================================= #

#  In some instances, you might wish to discard the first value read.
#  In such cases, simply ignore the $REPLY variable.

{ # Code block.
read            # Line 1, to be discarded.
read line2      # Line 2, saved in variable.
  } <$0
echo "Line 2 of this script is:"
echo "$line2"   #   # read-novar.sh
echo            #   #!/bin/bash  line discarded.

# See also the soundcard-on.sh script.

exit 0