NAME    [Toc]    [Back]

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

LIBRARY    [Toc]    [Back]

     Standard C Library (libc, -lc)

SYNOPSIS    [Toc]    [Back]

     #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    [Toc]    [Back]

     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 special
 value 0.

     The string may 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 value in the
     obvious manner, stopping at the end of the string or at the first character
 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    [Toc]    [Back]

     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.

ERRORS    [Toc]    [Back]

     [EINVAL]		The value of base is not supported or no conversion
			could be performed.

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

SEE ALSO    [Toc]    [Back]

     strtol(3), wcstoul(3)

STANDARDS    [Toc]    [Back]

     The strtoul() function conforms to ISO/IEC 9899:1990 (``ISO C89'').  The
     strtoull() and strtoumax() functions conform to ISO/IEC 9899:1999
     (``ISO C99'').  The BSD strtouq() function is deprecated.


FreeBSD 5.2.1		       November 28, 2001		 FreeBSD 5.2.1