3.9.       99

 . ,  , ,   
 , .        ,
    .        -
   .       
 .     ,     -
 .          -
.        ( -
  )    . 3.12.

3.9.1.     
   fork (),  (), system ()
 posix_spawn()

 fork (), fork-exec  posix_spawn ()   
.    fork ()   
.        
( )  (PID) -  ( ) 
, ,     .    -
  ;      
,      fork ().  
   fork-exec-   -
     .    ()  
(..   ),     
 .  posix_spawn()    
  .   (PID),  ( -
)  posix_spawn ()  ,   -
 ,     .  -
  posix_spawn()    . -
 system ()    .   
,        .
        ,   -
     system ()   .

3.9.2.  wait ()

 ,   wait (),   -
   ,     .   
        -
,     -"".  wait ()  -
    .  status    , -
     .   
  ,          -
,  wait ()        
  .        
  wait (),    .  -
      ,     .