int
main ( void )
{

  char          string[20] =  "ah ah pouet prout" ;
  regex_t *     preg = ( regex_t * ) malloc ( sizeof ( regex_t ) ) ;
  size_t        nmatch ;
  regmatch_t    pmatch[50] ;
  int           i, j ;

  if ( regcomp ( preg, "\\w{2} pouet", REG_EXTENDED ) )
    printf ( "error regcomp\n" ) ;

  if ( regexec ( preg, string, nmatch, pmatch, 0 ) )
    printf ( "error regexec\n" ) ;

  for ( i=0; i<50; i++ ){
    if ( (pmatch[i]).rm_so == 0 && (pmatch[i]).rm_eo == 0 ){
      i = 50 ;
      break ;
    }

    for ( j=(pmatch[i]).rm_so; j<(pmatch[i]).rm_eo; j++ )
      putc ( string[j], stdout ) ;

    putc ( '\n', stdout ) ;
  }

  return 0 ;
}