 0  true ( false)     -
.      0  false ( true),   -
    .   echo   , -
    ,   .    
EOF ("end of file")  read    false,  
  while,    .

      spell_check,   -
 ,    ,   
. ,      Blankenship  Klimowski, Attorneys,
      Blankenship  Klimowski.   -
,   spell_check      memo 
       Blankenship  Klimowski:

$ aspell -I < memo

Blankenship

Klimowski

targat

the

$ cat word_list

Blankenship

Klimowski

$ spell check word_list memo

targat

hte

    aspell    /usr/share/

doc/aspell/man-html/index.html (FEDORA)  /usr/share/doc/aspell-0.*/man-html/
index. html(RHEL).

until

 until  while  ,
    -
.  . 28.6 ,  
until      ,
 -   
 true.  while  ,
 -  true 
 .  until
  :

. 28.6. -  until

until -
do


done

     until   read.
     , - -
 ,       :

 28.   Bourne Again Shell 885

