strtoul(3STDC)

NAME | SYNOPSIS | API RESTRICTIONS | DESCRIPTION | RETURN VALUES | ERRORS | ATTRIBUTES | SEE ALSO | STANDARDS

NAME

strtoul- convert a string to an unsigned long or uquad_t integer

SYNOPSIS

$(NUCLEUS_DIR)/lib/classix/libsys.s.a
#include <stdlib.h>
#include <limits.h>

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

API RESTRICTIONS

The function or functions documented here may not be used safely in all application contexts with all APIs provided in the ChorusOS 5.0 product.

See API(5FEA) for details.

DESCRIPTION

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

The string may begin with an arbitrary amount of white space (as determined by isspace(3STDC)) 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 stopping at the end of the string or at the first character that does not produce a valid digit in the base given. (In bases above 10, the letter A in either upper or lowercase represents 10, B represents 11, and so forth, with Z representing 35.)

If endptr is not nil, 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 will have been valid.)

RETURN VALUES

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 that case, strtoul() returns ULONG_MAX and, in contexts where it is supported, sets the global variable errno to ERANGE.

ERRORS

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

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Interface Stability	Evolving

SEE ALSO

strtol(3STDC)

STANDARDS

The strtoul() function conforms to ANSI-C.

NAME | SYNOPSIS | API RESTRICTIONS | DESCRIPTION | RETURN VALUES | ERRORS | ATTRIBUTES | SEE ALSO | STANDARDS