Function            atrim - trims leading and trailing blanks

  Syntax              char *atrim(char *source);

  Prototype in        stringhk.h

  Remarks             remove leading and trailing blanks in a string. The
                      string passed to atrim (source) is modified.

  Return value        returns a pointer to source.

  Example             #include <stringhk.h>
                      #include <stdio.h>            /* for the printf */

                      main()
                      {
                           char msg[25] = "  Hello everyone   ";
                           printf("String [%s]\n",msg);
                           printf("atrim  [%s]\n",atrim(msg));
                      }

  Program output      String [  Hello everyone   ]
                      atrim  [Hello everyone]