external/ibm-public/postfix/dist/src/util/alldig.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      alldig 3
   6 /* SUMMARY
   7 /*      predicate if string is all numerical
   8 /* SYNOPSIS
   9 /*      #include <stringops.h>
  10 /*
  11 /*      int     alldig(string)
  12 /*      const char *string;
  13 /* DESCRIPTION
  14 /*      alldig() determines if its argument is an all-numerical string.
  15 /* SEE ALSO
  16 /*      An alldig() routine appears in Brian W. Kernighan, P.J. Plauger:
  17 /*      "Software Tools", Addison-Wesley 1976.
  18 /* LICENSE
  19 /* .ad
  20 /* .fi
  21 /*      The Secure Mailer license must be distributed with this software.
  22 /* AUTHOR(S)
  23 /*      Wietse Venema
  24 /*      IBM T.J. Watson Research
  25 /*      P.O. Box 704
  26 /*      Yorktown Heights, NY 10598, USA
  27 /*--*/
  28
  29 /* System library. */
  30
  31 #include <sys_defs.h>
  32 #include <ctype.h>
  33
  34 /* Utility library. */
  35
  36 #include <stringops.h>
  37
  38 /* alldig - return true if string is all digits */
  39
  40 int     alldig(const char *string)
  41 {
  42     const char *cp;
  43
  44     if (*string == 0)
  45         return (0);
  46     for (cp = string; *cp != 0; cp++)
  47         if (!ISDIGIT(*cp))
  48             return (0);
  49     return (1);
  50 }