strtoul

STRTOUL(3)                  Linux Programmer's Manual                 STRTOUL(3)



NAME
       strtoul - convert a string to an unsigned long integer.

SYNOPSIS
       #include <stdlib.h>

       unsigned long int strtoul(const char *nptr, char **endptr,
       int base)

DESCRIPTION
       The strtoul() function converts the string in nptr to an unsigned long
       integer value according to the given base, which must be between 2 and 36
       inclusive, or be the special value 0.

       The string must begin with an arbitrary amount of white space (as
       determined by isspace(3)) followed by a single optional `+' or `-' sign.
       If base is zero or 16, the string may then include a `0x' prefix, and the
       number will be read in base 16; otherwise, a zero base is taken as 10
       (decimal) unless the next character is `0', in which case it is taken as
       8 (octal).

       The remainder of the string is converted to an unsigned long int value in
       the obvious manner, stopping at the first character which is not a valid
       digit in the given base.  (In bases above 10, the letter `A' in either
       upper or lower case represents 10, `B' represents 11, and so forth, with
       `Z' representing 35.)

       If endptr is not NULL, strtoul() stores the address of the first invalid
       character in *endptr.  If there were no digits at all, strtoul() stores
       the original value of nptr in *endptr.  (Thus, if *nptr is not `\0' but
       **endptr is `\0' on return, the entire string is valid.)

RETURN VALUE
       The strtoul() function returns either the result of the conversion or, if
       there was a leading minus sign, the negation of the result of the
       conversion, unless the original (non-negated) value would overflow; in
       the latter case, strtoul() returns ULONG_MAX and sets the global variable
       errno to ERANGE.

ERRORS
       ERANGE The given string was out of range; the value converted has been
              clamped.

CONFORMING TO
       SVID 3, BSD 4.3, ISO 9899

SEE ALSO
       atof(3), atoi(3), atol(3), strtod(3), strtol(3)

BUGS
       Ignores the current locale.



GNU                              March 29, 1993                       STRTOUL(3)