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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  de-
       termined	 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 in-
       valid character in *endptr.  If there were no digits at all,  strtoul()
       stores  the original value of nptr in *endptr (and returns 0).  In par-
       ticular,	if *nptr is not	`\0' but **endptr is `\0' on return,  the  en-
       tire string is valid.

       The  strtoull() function	works just like	the strtoul() function but re-
       turns 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  ac-
       cepted.	 (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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