#include "utility.h"

int valchars(string,valid_characters)
/*============================================================================*/
/* PURPOSE: DETERMINE IF A STRING IS COMPOSED OF VALID CHARACTERS.
/* INPUTS:
/*	STRING			STRING CONTAINING QUESTIONABLE CHARACTERS.
/*	VALID_CHARACTERS	LIST OF VALID CHARACTERS.
/* OUTPUTS:
/*	FUNCTION VALUE		TRUE IF STRING IS COMPOSED OF VALID CHARACTERS,
/*				FALSE OTHERWISE.
/* WRITTEN: M.V.GRIESHABER
/* LAST MODIFICATION: 11 JUNE 1991 MVG
*/
   char string[];
   char valid_characters[];
   {
   int i;			/* LOOP INDEX: WHICH CHAR IN STRING. */
   int j;			/* LOOP INDEX: WHICH CHAR IN VALID CHARS. */
   int good_char;		/* FLAG: WHETHER CHAR IS VALID OR NOT. */

   for (i=0; i<strlen(string); i++)
      {
      good_char=FALSE;
      for (j=0; j<strlen(valid_characters); j++)
         {
         if (string[i]==valid_characters[j]) good_char=TRUE;
         }
      if (! good_char) return(FALSE);
      }
      return(TRUE);
   }