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

NAME
       strtoul,	strtoull, strtouq - convert a string to	an unsigned long inte-
       ger

SYNOPSIS
       #include	<stdlib.h>

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

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

DESCRIPTION
       The strtoul() function converts the initial part	of 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'  pre-
       fix,  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,  str-
       toul()  stores  the  original value of nptr in *endptr (and returns 0).
       In particular, if *nptr is not `\0' but **endptr	is `\0'	on return, the
       entire string is	valid.

       The  strtoull()	function  works	 just  like the	strtoul() function but
       returns an unsigned long	long integer value.

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 vari-
       able errno to ERANGE.  Precisely	the same holds	for  strtoull()	 (with
       ULLONG_MAX instead of ULONG_MAX).

ERRORS
       ERANGE The resulting value was out of range.

       EINVAL (not in C99) The given base contains an unsupported value.

       The  implementation  may	also set errno to EINVAL in case no conversion
       was performed (no digits	seen, and 0 returned).

NOTES
       In locales other	than  the  "C"	locale,	 also  other  strings  may  be
       accepted.   (For	example, the thousands separator of the	current	locale
       may be supported.)

       BSD also	has

	   u_quad_t
	   strtouq(const char *nptr, char **endptr, int	base);

       with completely analogous definition.  Depending	on the wordsize	of the
       current	architecture,  this may	be equivalent to strtoull() or to str-
       toul().

CONFORMING TO
       strtoul() conforms to SVID 3, BSD 4.3, ISO 9899 (C99)  and  POSIX,  and
       strtoull() to ISO 9899 (C99) and	POSIX-2001.

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

GNU				  2002-05-30			    STRTOUL(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | NOTES | CONFORMING TO | SEE ALSO

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