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STRTOUL(3)	       FreeBSD Library Functions Manual		    STRTOUL(3)

NAME
     strtoul, strtoull,	strtoumax, strtouq -- convert a	string to an unsigned
     long, unsigned long long, uintmax_t, or u_quad_t integer

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <stdlib.h>
     #include <limits.h>

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

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

     #include <inttypes.h>

     uintmax_t
     strtoumax(const char * restrict nptr, char	** restrict endptr, int	base);

     #include <sys/types.h>
     #include <stdlib.h>
     #include <limits.h>

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

DESCRIPTION
     The strtoul() function converts the string	in nptr	to an unsigned long
     value.  The strtoull() function converts the string in nptr to an
     unsigned long long	value.	The strtoumax()	function converts the string
     in	nptr to	an uintmax_t value.  The strtouq() function converts the
     string in nptr to a u_quad_t value.  The conversion is done according to
     the given base, which must	be between 2 and 36 inclusive, or be the spe-
     cial value	0.

     The string	may begin with an arbitrary amount of white space (as deter-
     mined 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 value	in the
     obvious manner, stopping at the end of the	string or at the first charac-
     ter that does not produce 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, however, strtoul()
     stores the	original value of nptr in *endptr.  (Thus, if *nptr is not
     `\0' but **endptr is `\0' on return, the entire string was	valid.)

RETURN VALUES
     The strtoul(), strtoull(),	strtoumax() and	strtouq() functions return
     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,	strtoull() returns ULLONG_MAX, strtoumax() returns
     UINTMAX_MAX, and strtouq()	returns	ULLONG_MAX.  In	all cases, errno is
     set to ERANGE.  If	no conversion could be performed, 0 is returned	and
     the global	variable errno is set to EINVAL	(the last feature is not por-
     table across all platforms).

ERRORS
     [EINVAL]		The value of base is not supported or no conversion
			could be performed (the	last feature is	not portable
			across all platforms).

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

SEE ALSO
     strtol(3),	wcstoul(3)

STANDARDS
     The strtoul() function conforms to	ISO/IEC	9899:1990 (``ISO C90'').  The
     strtoull()	and strtoumax()	functions conform to ISO/IEC 9899:1999
     (``ISO C99'').  The BSD strtouq() function	is deprecated.

FreeBSD	6.0		       November	28, 2001		   FreeBSD 6.0

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | SEE ALSO | STANDARDS

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