#!/bin/bash
# ¾ÕÀÇ ¿¹Á¦¿Í ¶È°°À¸³ª "until" ·çÆ®¸¦ »ç¿ë.

if [ -z "$1" ]
then
  Filename=names.data         # ÆÄÀÏÀ̸§ÀÌ ÁöÁ¤µÇÁö ¾Ê¾ÒÀ» °æ¿ìÀÇ ±âº»°ª.
else
  Filename=$1
fi  

# while [ "$name" != Smith ]
until [ "$name" = Smith ]     # != ¸¦ = ·Î ¹Ù²ãÁÖ¼¼¿ä.
do
  read name                   # Ç¥ÁØÀÔ·ÂÀÌ ¾Æ´Ï¶ó $Filename ¿¡¼­ ÀÐ¾î µéÀÔ´Ï´Ù.
  echo $name
done <"$Filename"             # Ç¥ÁØÀÔ·ÂÀ» $Filename ÆÄÀÏ·Î ÀçÁöÇâ.
#    ^^^^^^^^^^^^

# ¾Õ ¿¹Á¦ÀÇ "while" ·çÇÁ¿Í ¶È°°Àº °á°ú°¡ ³ª¿É´Ï´Ù.

exit 0