Kernel Functions for Drivers                      ddistrtoul(9F)



NAME
     ddistrtoul - String conversion functions

SYNOPSIS
     #include 
     #include 

     int ddistrtoul(const char *str, char **endptr, int base,
          unsigned long *result);


INTERFACE LEVEL
     Solaris DI specific (Solaris DI)

PARAMETERS
     str        Pointer to a character string to be converted.


     endptr     Post-conversion  final  string  of   unrecognized
                characters.


     base       Radix used for conversion.


     result     Pointer to variable which contains the  converted
                value.


DESCRIPTION
     The ddistrtoul() function converts the initial  portion  of
     the  string  pointed  to  by str to a type unsigned long int
     representation and stores the converted value in result.


     The  function first decomposes the input string  into  three
     parts:

         1.   An initial (possibly empty) sequence of white-space
              characters (' ', '\t', '\n', '\r', '\f')

         2.   A  subject  sequence  interpreted  as  an   integer
              represented  in  some radix determined by the value
              of base

         3.   A final  string of one or more unrecognized charac-
              ters,  including  the  terminating null byte of the
              input string.


     The ddistrtoul() function then attempts to convert the sub-
     ject sequence to an unsigned integer and returns the result.



SunOS 5.11          Last change: 13 May 2004                    1






Kernel Functions for Drivers                      ddistrtoul(9F)



     If the value of base is 0, the expected form of the  subject
     sequence  is  that  of a decimal constant, octal constant or
     hexadecimal constant, any of which may be preceded by a plus
     ("]")  or minus ("-") sign. A decimal constant begins with a
     non-zero digit,  and  consists  of  a  sequence  of  decimal
     digits. An octal constant consists  of  the prefix 0 option-
     ally followed by a sequence of the digits 0  to  7  only.  A
     hexadecimal   constant  consists of the prefix 0x or 0X fol-
     lowed by a sequence of the decimal digits and letters a  (or
     A) to f (or F) with values 10 to 15 respectively.


     If the value of base is between 2 and 36, the expected  form
     of  the subject sequence is a sequence of letters and digits
     representing an integer with the radix  specified  by  base,
     optionally  preceded  by  a  plus or minus sign. The letters
     from a (or A) to z (or Z) inclusive are ascribed the  values
     10  to  35  and  only letters whose ascribed values are less
     than that of base are permitted. If the value of base is 16,
     the  characters 0x or 0X may optionally precede the sequence
     of letters and digits, following the sign if present.


     The subject sequence is  defined   as  the  longest  initial
     subsequence  of  the  input  string, starting with the first
     non-white-space character that is of the expected form.  The
     subject  sequence contains no characters if the input string
     is empty or consists entirely of white-space characters,  or
     if  the first non-white-space character is other than a sign
     or a permissible letter or digit.


     If the subject sequence has the expected form and the  value
     of  base  is 0, the sequence of characters starting with the
     first digit is interpreted as an integer  constant.  If  the
     subject sequence has the expected form and the value of base
     is between 2 and 36, it is used as the base for  conversion,
     ascribing   to  each letter its value as given above. If the
     subject sequence begins with a minus sign, the value result-
     ing  from  the conversion is negated. A pointer to the final
     string is stored in the object pointed to  by  endptr,  pro-
     vided that endptr is not a null pointer.


     If the subject sequence  is  empty  or  does  not  have  the
     expected   form, no conversion is performed and the value of
     str is stored in the object pointed to by  endptr,  provided
     that endptr is not a null pointer.

RETURN VALUES
     Upon successful  completion,  ddistrtoul()  returns  0  and
     stores  the  converted  value in result. If no conversion is



SunOS 5.11          Last change: 13 May 2004                    2






Kernel Functions for Drivers                      ddistrtoul(9F)



     performed due to invalid base, ddistrtoul() returns  EINVAL
     and the variable pointed by result is not changed.


     If the correct value is outside the range  of  representable
     values,  ddistrtoul()  returns ERANGE and the value pointed
     to by result is not changed.

CONTEXT
     The ddistrtoul() function may be called from  user,  kernel
     or interrupt context.

SEE ALSO
     Writing Device Drivers









































SunOS 5.11          Last change: 13 May 2004                    3