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<h4 class="subsection">10.4.4 <code>wordexp</code> Example</h4>

<p>Here is an example of using <code>wordexp</code> to expand several strings
and use the results to run a shell command.  It also shows the use of
<code>WRDE_APPEND</code> to concatenate the expansions and of <code>wordfree</code>
to free the space allocated by <code>wordexp</code>.

<pre class="smallexample">     int
     expand_and_execute (const char *program, const char **options)
     {
       wordexp_t result;
       pid_t pid
       int status, i;
     
       /* <span class="roman">Expand the string for the program to run.</span>  */
       switch (wordexp (program, &amp;result, 0))
         {
         case 0:			/* <span class="roman">Successful</span>.  */
           break;
         case WRDE_NOSPACE:
           /* <span class="roman">If the error was </span><code>WRDE_NOSPACE</code><span class="roman">,</span>
              <span class="roman">then perhaps part of the result was allocated.</span>  */
           wordfree (&amp;result);
         default:                    /* <span class="roman">Some other error.</span>  */
           return -1;
         }
     
       /* <span class="roman">Expand the strings specified for the arguments.</span>  */
       for (i = 0; options[i] != NULL; i++)
         {
           if (wordexp (options[i], &amp;result, WRDE_APPEND))
             {
               wordfree (&amp;result);
               return -1;
             }
         }
     
       pid = fork ();
       if (pid == 0)
         {
           /* <span class="roman">This is the child process.  Execute the command.</span> */
           execv (result.we_wordv[0], result.we_wordv);
           exit (EXIT_FAILURE);
         }
       else if (pid &lt; 0)
         /* <span class="roman">The fork failed.  Report failure.</span>  */
         status = -1;
       else
         /* <span class="roman">This is the parent process.  Wait for the child to complete.</span>  */
         if (waitpid (pid, &amp;status, 0) != pid)
           status = -1;
     
       wordfree (&amp;result);
       return status;
     }
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